Intelligent blade with functions of monitoring cracking and heating deicing and processing method thereof

Abstract

The application discloses an intelligent blade with functions of monitoring cracking and heating deicing and a processing method thereof, and relates to the technical field of wind turbine blades. The monitoring cloth is arranged, so that the effect of monitoring cracking and heating deicing is achieved during the operation of the blade. The pre-embedding of the optical fiber in the blade improves the use efficiency of the sensor, monitors the change data of the temperature and the strain load of the blade from production to use, and achieves better monitoring effect. In addition, the data of various parameters of the blade can be recorded in the factory, which lays a foundation for later maintenance. The laying of the one-way heat-conducting reflective film reduces the inner cavity temperature of the blade in summer. In winter, the one-way heat-conducting reflective film and the monitoring cloth jointly achieve better heating deicing effect. The material of the shell is modified resin with good heat-conducting performance, which increases the heat conductivity of the blade, is beneficial to the heating of the carbon fiber wire bundle, and reduces the requirement for the density of the carbon fiber wire bundle in the monitoring cloth after improving the heat conductivity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wind turbine blades, in particular to an intelligent blade with crack monitoring and heating deicing functions and a processing method thereof. BACKGROUND

[0002] The principle of wind power generation is to use wind to drive the wind turbine blade to rotate, and then use the speed increaser to increase the rotation speed to promote the generator to generate electricity. According to the wind turbine technology, the wind can start to generate electricity. Wind power generation is becoming a general trend in the world because wind power generation has no fuel problem and will not produce radiation or air pollution. Wind power generation is very popular in Finland, Denmark and other countries. Our country also advocates small wind power generation system in the western region. The small wind power generation system is not composed of only a generator head, but a small system with certain scientific and technological content; the wind power generator + charger + digital inverter, the wind power generator is composed of a head, a rotating body, a tail wing and a blade, and each part is very important.

[0003] Among them, the blade is used to accept wind power and convert it into electric energy through the head, and the blade is very important. However, cracks often occur in the blade during long-term operation. If these cracks are not treated in time, the cracks will further expand, eventually leading to high repair and maintenance costs. At present, due to differences in machine groups, wind fields and blades, conventional load and defect monitoring technology cannot timely identify the initial crack generation, especially in local areas.

[0004] The load and temperature of the blade are constantly changing during production, transportation and operation, and the external monitoring system is often used to monitor the strain, load and temperature changes of the blade during production, transportation and operation. The external monitoring system will cause damage to the blade to a certain extent, and the material cost and installation cost are high.

[0005] During the operation of the blade, the temperature in the inner cavity of the blade is too high in summer, and the surface of the blade is easy to freeze in winter, which will affect the normal operation of the blade. After a long time in a high temperature or surface icing state, the blade is easy to be damaged, which reduces the service life of the blade, and the cost of artificial deicing is too high.

[0006] Therefore, an intelligent blade capable of real-time monitoring of the blade state and having a cooling and deicing function is needed. SUMMARY

[0007] In view of the problems in the prior art, the present application solves the problems by using the following technical structure.

[0008] To achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0009] The application discloses an intelligent blade with functions of monitoring cracking and heating deicing, comprising a blade body, wherein the blade body comprises a shell, an abdominal plate, the shell is divided into an upper shell and a lower shell, and the abdominal plate is arranged between the upper shell and the lower shell.

[0010] A laying layer is arranged in the shell wall, and the laying layer comprises an optical fiber layer and a monitoring cloth layer.

[0011] The optical fiber layer comprises a plurality of optical fiber cloths, a plurality of optical fiber sensors are arranged on each of the plurality of optical fiber cloths, and the plurality of optical fiber sensors are connected with external equipment through optical fibers.

[0012] The monitoring cloth layer covers the whole shell, the monitoring cloth layer comprises a plurality of monitoring cloths, a plurality of carbon fiber bundles are arranged on each of the plurality of monitoring cloths, the plurality of carbon fiber bundles are connected with an external power supply with switchable output power through connecting wires, and the plurality of carbon fiber bundles are connected with external acquisition equipment for monitoring whether a circuit composed of the plurality of carbon fiber bundles is abnormal through the connecting wires.

[0013] Further features are,

[0014] The monitoring cloth layer is provided with two layers, an isolation layer is arranged between the two monitoring cloth layers, and the carbon fiber bundles on the two monitoring cloth layers are in orthogonal distribution.

[0015] There is only one carbon fiber bundle on one monitoring cloth, and the carbon fiber bundle is in serpentine distribution and covers the whole monitoring cloth.

[0016] A heat-conducting reflective film for reflecting sunlight is arranged on the inner cavity wall of the front edge of the shell.

[0017] The abdominal plate comprises a small abdominal plate and a main abdominal plate, and the upper and lower ends of the small abdominal plate and the main abdominal plate are connected with the top surface and the bottom surface of the inner cavity of the shell respectively.

[0018] The optical fiber cloth and the monitoring cloth are both made of biaxial glass fiber cloth.

[0019] The parts of the blade, which need to observe stress, strain and temperature, are all provided with the optical fiber cloth.

[0020] The upper shell and the lower shell are made of modified resin with heat conductivity.

[0021] A processing method of the intelligent blade with functions of monitoring cracking and heating deicing, comprising the following steps:

[0022] S1: arranging the optical fiber layer and the monitoring cloth layer in a mold cavity of the upper shell and the lower shell, and reserving an optical fiber interface and a monitoring interface for connecting external equipment;

[0023] S2: Preform each component of the blade by vacuum infusion modified resin, and connect the optical fiber layer interface to the distributed optical fiber monitoring system during curing;

[0024] S3: Demold the preform of each component of the blade, and lay the heat-conducting reflective film in the inner cavities of the upper and lower shells;

[0025] S4: Assemble each component of the blade, and close the mold of the upper and lower shells, lay the optical fiber at the bonding position of the closed mold, reserve the optical fiber interface, and connect the optical fiber interface to the distributed optical fiber monitoring system during curing of the closed mold;

[0026] S5: After the mold is closed, lay the edge cover at the joint, and set a layer of monitoring cloth in the edge cover.

[0027] The above structure of the present application can achieve the following beneficial effects:

[0028] (1) By setting the monitoring cloth, the effect of monitoring cracking and heating deicing during the operation of the blade is achieved, the pre-embedded optical fiber in the blade improves the use efficiency of the sensor, and the temperature and strain load change data of the blade from production to use are monitored, better monitoring effect is achieved, and the data of each parameter of the blade can be recorded in the factory, laying a foundation for later maintenance, through the laying of the one-way heat-conducting reflective film, the inner cavity temperature of the blade is reduced in summer, and better heating deicing effect is achieved in winter under the joint action of the monitoring cloth, the material of the shell is modified resin with good heat-conducting performance, the heat-conducting property of the blade is increased, the carbon fiber wire bundle heating is facilitated, and the requirement for the carbon fiber wire bundle density in the monitoring cloth is reduced after improving the heat-conducting property. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a cross-sectional structure schematic diagram of the present embodiment;

[0030] Figure 2 It is a monitoring cloth structure schematic diagram in the present embodiment;

[0031] Figure 3 It is a circuit structure schematic diagram of the carbon fiber wire bundle connection mode one in the present embodiment;

[0032] Figure 4 It is a circuit structure schematic diagram of the carbon fiber wire bundle connection mode two in the present embodiment;

[0033] Figure 5 It is a monitoring cloth other implementable structure schematic diagram in the present embodiment.

[0034] In the figure: 1, shell; 2, web; 21, small web; 22, main web; 3, heat-conducting reflective film; 4, layup. DETAILED DESCRIPTION

[0035] Embodiment one, refer toFigures 1-5 The intelligent blade with the functions of monitoring cracking and heating deicing shown in the figure comprises a blade body, the blade body comprising a shell 1, a web plate 2, the shell 1 being divided into an upper shell and a lower shell, the web plate 2 being installed between the upper shell and the lower shell, the web plate 2 comprising a small web plate 21 and a main web plate 22, the upper and lower ends of the small web plate 21 and the main web plate 22 being connected with the top surface and the bottom surface of the inner cavity of the shell 1 respectively, and a heat-conducting reflective film 3 for reflecting sunlight being laid on the cavity wall of the inner cavity of the front edge (windward end) of the shell 1;

[0036] A laying layer 4 is laid in the shell wall, the laying layer 4 comprising an optical fiber layer and a monitoring cloth layer;

[0037] The optical fiber layer comprises a plurality of optical fiber cloths, a plurality of optical fiber sensors are arranged on each of the plurality of optical fiber cloths, the plurality of optical fiber sensors are connected with external equipment through optical fibers, and the optical fiber cloths are laid on parts of the blade where stress, strain and temperature need to be observed;

[0038] The monitoring cloth layer covers the entire shell 1, and in actual use, the monitoring cloth layer can also be laid in key areas (desired areas) only, the monitoring cloth layer comprises a plurality of monitoring cloths, a plurality of carbon fiber wire bundles are arranged on each of the plurality of monitoring cloths, the plurality of carbon fiber wire bundles are connected with an external power supply with switchable output power through connecting wires, the plurality of carbon fiber wire bundles are connected with external acquisition equipment for monitoring whether the circuit composed of the plurality of carbon fiber wire bundles is abnormal through connecting wires, and the optical fiber cloth and the monitoring cloth are both biaxial glass fiber cloth, in actual production, biaxial glass fiber cloth is preferred, and short-cut felt, triaxial cloth or unidirectional cloth can also be used.

[0039] The monitoring cloth layer is provided with two layers, an isolation layer is arranged between the two monitoring cloth layers, the carbon fiber wire bundles on the two monitoring cloths at the same position are in orthogonal distribution, regardless of the cracking direction of the blade, the cracking can be monitored at any time, and in actual application, if it is clear that the blade has only one cracking direction, only one layer of carbon fiber wire bundle and the monitoring cloth layer perpendicular to the cracking direction need to be arranged.

[0040] There is only one carbon fiber wire bundle on one monitoring cloth, the carbon fiber wire bundle is in serpentine distribution and covers the entire monitoring cloth, and the monitoring accuracy of the blade for cracking is further optimized.

[0041] Based on the above features, in actual use, the external power supply adopts 24V power supply, all the carbon fiber wire bundles covered on the blade are connected with the external power supply and the acquisition and comparison module through wires, the connection modes include but are not limited to the following two connection modes, connection mode one: the carbon fiber wire bundles are connected together in parallel through wires, and the circuit is as shown in the following figure Figure 3As shown, the voltage value of the circuit is constant when it is working normally. If a resistance breaks during the operation of the blade, the voltage of the parallel circuit at this position increases, and the voltage of the sampling resistance Rr decreases. The breakage of other areas will also cause this situation. The voltage of the resistance collected by the collection comparison module is compared with the normal voltage value to determine whether the blade has a problem. The system sends an alarm, and the blade is repaired in time.

[0042] Connection mode two: the carbon fiber wire harness is connected together in series to form a circuit as shown. Figure 4 As shown, if the circuit breaks in the series circuit, the current of the branch is zero. It can be known that when the resistance breaks in the series network of the carbon fiber wire harness in different areas, the current of the branch is zero. The blade in the area with zero current breaks, which is determined by the current monitoring collection module. It can be known that when the resistance breaks in the series network of the carbon fiber wire harness in different areas, the current of the branch is zero. The blade in the area with zero current breaks, which is determined by the current monitoring collection module.

[0043] When the blade surface is iced in winter, the wind turbine control system determines that the external blade is iced. When the external humidity and temperature meet the icing conditions, the control device switches to the 220-volt power supply equipment through the adjustment of the control switch. The high voltage makes the carbon fiber wire harness heat, which heats the monitoring cloth. The monitoring cloth and the heat-conducting reflective film laid in the inner cavity cooperate to raise the temperature of the blade surface, which avoids icing and deicing, improves the power generation efficiency of the wind turbine, and restores the monitoring blade cracking collection state through the switching circuit when the external system determines that the icing condition is not met.

[0044] The application pre-buries an optical fiber sensor in the blade. The optical fiber sensor is pre-buried in the blade during the manufacturing process of the blade. The distributed optical fiber measurement technology monitors the strain, load and temperature change in the production and transportation process of the blade. The pre-buried reduces the damage of the external monitoring system to the blade and saves the installation cost. The distributed optical fiber monitoring technology uses ordinary bare optical fiber as a sensor, has the characteristics of low cost and dense measuring points, the lead wire is connected through a fiber joint, and is connected to a distributed optical fiber demodulator. The temperature, deformation, strain and other information of the optical fiber at different distances can be obtained. Moreover, the bare optical fiber is thin and low in cost, similar to the blade glass fiber cloth material, and can be easily implemented by being woven into double-axis glass fiber cloth during the production process. Compared with the conventional pre-buried sensor, the size impact can be ignored. The undamaged optical fiber can be selected as a sensor, and the active resin is used to paste it on the blade layer (not limited to this way). After the subsequent vacuum treatment, the optical fiber and the blade layer are combined without damage.

[0045] The application installs a heat-conducting reflective film 3 on the inner wall of the blade cavity. The heat-conducting reflective film 3 can reflect solar radiation out of the blade, reduce the temperature of the blade cavity in summer, and increase the deicing effect by reflecting the heating source radiation energy in winter. The heat-conducting reflective film is bonded by improved resin, and the improved resin is selected to have high heat-conducting properties. When deicing by heating, the heat can be quickly conducted to the outside of the blade, reducing the icing time. The one-way heat-conducting reflective film 3 can provide the effects of heat dissipation in summer and deicing in winter.

[0046] The upper shell and the lower shell are made of modified resin with heat conductivity (non-conductive heat-conductive filler such as silicon is added to conventional epoxy resin), and are combined with glass steel or carbon fiber. The modified resin increases the heat conductivity of the blade, which is beneficial to carbon fiber wire heating or hot air deicing. After increasing the heat conductivity, the requirement for the carbon fiber wire density of the monitoring cloth is reduced. Because of the increased heat conductivity, the monitoring cloth with lower carbon fiber wire can be used as a heating device.

[0047] Further optimization is that the monitoring cloth can also be pasted on the blade after damage and repair during long-term operation to monitor the safety of the blade. The carbon fiber wire on the repaired monitoring cloth is preferably woven in a ring-shaped direction in the biaxial fiberglass cloth (as shown in Figure 5 The woven method can detect cracks in any direction, so that the monitoring circuit can monitor the change of the electrical signal and alarm in time when the blade is damaged. Two monitoring cloths can also be arranged orthogonally and overlapped to achieve the same function of monitoring the cracks of the blade.

[0048] The blade can be connected to a test device at the root when it is shipped. The actual load and deformation of the blade are obtained by weighing the hoisting load and the weight center of the blade, and the weight, center of gravity, length, and maximum chord length of the blade are measured. The data are recorded, the measurement signals are obtained through internal sensors, and the calibration coefficient is obtained through comparison and analysis. After the data are sorted, they are written into the root junction box processor of the blade, which is convenient for the later operation monitoring of the blade. During the transportation of the blade, the signals in the junction box can be selectively connected to the vehicle equipment to monitor the transportation state and avoid damage during transportation.

[0049] A processing method of an intelligent blade with monitoring cracking and deicing functions, comprising the steps of:

[0050] S1: The optical fiber layer and the monitoring cloth layer are arranged in the mold cavity of the upper shell and the lower shell, and the optical fiber interface and the monitoring interface for connecting external devices are reserved, the blade shell is laid with cloth and the prefabricated part is placed, the materials and sizes used for laying are different, the monitoring cloth is laid for the layers that need to be monitored, such as the secondary outer layer and the secondary inner layer of the shell, the optical fiber cloth is laid in the area that needs to be monitored for strain and temperature, and the optical fiber cloth is adhered to the laying layer by using an adhesive, which can avoid the sliding of the biaxial glass fiber cloth, keep the flatness, and not affect the infusion quality, the monitoring cloth is connected to the signal line inside the shell through a wire, and the grid wires at both ends of the monitoring cloth are connected by a conductive material, so that the equivalent circuit of each grid wire becomes a series connection, a parallel connection or a mixed form of series and parallel connection;

[0051] S2: The blade components are prefabricated by vacuum infusion, the optical fiber layer interface is connected to the distributed optical fiber monitoring system during curing, the glass fiber is led out after the shell or large prefabricated part is vacuum infused, the undamaged optical fiber is detected and connected to the distributed optical fiber monitoring device, the temperature, deformation or strain at different positions of the blade during curing can be obtained, so that the process quality can be controlled, the local overheating or excessive stress change can be avoided, and in addition to the embedded ordinary optical fiber, the optical fiber with grating can also be embedded;

[0052] S3: The blade components are demolded, the heat-conducting reflective film 3 is laid in the inner cavity of the upper shell and the lower shell, and the heat-conducting reflective film 3 is laid on the inner side of the front edge direction of the shell 1 before molding, so as to reduce the radiation heating and improve the efficiency of the heating system. For deicing, the main focus is on the front edge area, so the energy needs to be concentrated in the front edge area;

[0053] S4: The blade components are assembled, the upper shell and the lower shell are molded, the optical fiber is laid at the bonding position of the mold, the optical fiber interface is reserved, the optical fiber interface is connected to the distributed optical fiber monitoring system during mold curing, and the optical fiber is laid at the bonding position of the mold, such as the front and rear edge bonding position, the web and the shell bonding position. After the mold is cured, the stress condition of the bonding area and the web can be obtained by connecting the optical fiber to the distributed optical fiber monitoring system, so as to avoid the web 2 cracking caused by lack of glue, poor curing or geometric interference, thereby realizing process control;

[0054] S5: After the mold is closed, the edge covering is laid at the joint.

[0055] The monitoring cloth and the optical fiber cloth can be embroidered on the biaxial glass fiber cloth by using a embroidery machine.

[0056] The working principle of the present application is that the bare optical fiber is embedded in the blade, which improves the use efficiency of the sensor and monitors the temperature and strain load change data of the blade from production to use, thereby achieving better monitoring effect, and the data of various parameters of the blade can be recorded in the factory, laying a foundation for later maintenance, and through the laying of the one-way heat conduction reflective film 3, the inner cavity temperature of the blade is reduced in summer, and better heating and deicing effect is achieved in cooperation with the monitoring cloth in winter, thereby improving the power generation capacity.

[0057] The above is only the preferred embodiment of the present application, and the present application is not limited to the above embodiments. It can be understood that other improvements and changes directly derived or thought by those skilled in the art without departing from the spirit and concept of the present application should be considered to be included in the protection scope of the present application.

Claims

1. An intelligent blade having a function of monitoring cracking and de-icing by heating, characterized by, The blade body comprises a shell (1) and a web (2), the shell (1) is divided into an upper shell and a lower shell, and the web (2) is arranged between the upper shell and the lower shell; A laying layer (4) is arranged in the shell wall, the laying layer (4) comprises an optical fiber layer and a monitoring cloth layer; The optical fiber layer comprises a plurality of optical fiber cloths, a plurality of optical fiber sensors are arranged on each of the optical fiber cloths, and the plurality of optical fiber sensors are connected with external equipment through optical fibers; The monitoring cloth layer covers the entire shell (1), the monitoring cloth layer comprises a plurality of monitoring cloths, a plurality of carbon fiber wire bundles are arranged on each of the monitoring cloths, the plurality of carbon fiber wire bundles are connected with an external power supply with switchable output power through connecting wires, and the plurality of carbon fiber wire bundles are connected with external acquisition equipment for monitoring whether a circuit composed of the plurality of carbon fiber wire bundles is abnormal through the connecting wires; The monitoring cloth layer is provided with two layers, an isolation layer is arranged between the two monitoring cloth layers, and the carbon fiber wire bundles on the two monitoring cloth layers are orthogonally distributed; There is only one carbon fiber wire bundle on one monitoring cloth, and the carbon fiber wire bundle is in a serpentine distribution and covers the entire monitoring cloth.

2. The smart blade with monitoring cracking and de-icing by heating function according to claim 1, characterized in that: A heat-conducting reflective film (3) for reflecting sunlight is arranged on the inner cavity wall of the front edge of the shell (1).

3. The smart blade with monitoring cracking and de-icing by heating function according to claim 1, characterized in that: The web (2) comprises a small web (21) and a main web (22), and the upper and lower ends of the small web (21) and the main web (22) are connected with the top surface and the bottom surface of the inner cavity of the shell (1) respectively.

4. The smart blade with monitoring cracking and de-icing by heating function according to claim 1, characterized in that: The optical fiber cloth and the monitoring cloth are both made of biaxial glass fiber cloth.

5. The smart blade with monitoring cracking and de-icing by heating function according to claim 1, characterized in that: The parts of the blade where stress, strain and temperature need to be observed are all provided with optical fiber cloths.

6. The smart blade with cracking and de-icing under heat monitoring function according to claim 1, characterized in that: The materials for manufacturing the upper shell and the lower shell comprise modified resin with heat conductivity.

7. A method of processing the smart blade with the functions of monitoring cracking and de-icing by heating according to any one of claims 1-6, characterized in that, The method comprises the following steps: S1: arranging the optical fiber layer and the monitoring cloth layer in the mold cavity of the upper shell and the lower shell, and reserving optical fiber interfaces and monitoring interfaces for connecting external equipment; S2: prefabricating each component of the blade by vacuum infusion, and connecting the optical fiber layer interfaces to a distributed optical fiber monitoring system during curing; S3: demolding the prefabricated parts of the blade, and arranging the heat-conducting reflective film (3) in the inner cavity of the front edge of the upper shell and the lower shell; S4: assembling each component of the blade, clamping the upper shell and the lower shell, arranging optical fibers at the clamping and bonding positions, reserving optical fiber interfaces, and connecting the optical fiber interfaces to the distributed optical fiber monitoring system during curing of the clamped shell; S5: after clamping, arranging a binding edge at the joint, and arranging a monitoring cloth layer in the binding edge.

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