Shi Ke re-introduced that the main features of the new generation of wind power generation technology are large-scale, regional and intelligent. The current research hotspots of the blade are also mainly reflected in adapting to the new trend of wind power technology. With the continuous expansion of the wind turbine's stand-alone capacity, the length of blades has also grown from about 20 meters to more than 60 meters. At present, the largest capacity wind turbine currently being developed in the world is 10 MW, and its blade length is more than 75 meters. This trend of large-scale blades has brought a series of new technical problems.
Different countries have different geographical and climatic characteristics, and also bring different requirements to the design of the blades. For example, in China's northern and southern regions, there are low temperatures, high winds, high temperature and humidity in the coastal areas, and more typhoons, and low wind speed in the wind field.
This regionalization requires the development of a series of regionalized technologies such as anti-typhoon blades, low-velocity blades, bionic blades, and low-noise blades. Shi reiterates that the next phase of wind power research in China will be based on the characteristics of Chinese wind resources. Product design and technology development.
In addition, he also pointed out that intelligence is also the trend of wind power technology development in the future. The continuous increase in the size and weight of wind turbine blades makes it more and more difficult to control the wind turbines. Therefore, smart blade technology is also one of the important directions for the research of a new generation of wind power technologies.
In fact, with the rapid development of the wind power industry, offshore wind power plays an important role in a new generation of wind power technology. He also pointed out that we should also pay attention to the new challenges brought about by the development of offshore wind power. At present, onshore wind farm equipment and construction technologies are basically mature. With the depletion of land-based wind energy resources in Europe, the main driving force for the future development of wind energy technology will come from the booming offshore wind power. Offshore wind power imposes higher requirements on the safety, reliability, ease of maintenance, and construction cost control of wind turbines. China has abundant offshore wind resources. With the gradual maturation of offshore wind power technology and the reduction of costs, offshore wind energy will inevitably become an important part of China's future energy structure.
“Floating wind turbines are the focus of R&D in foreign wind power industry in recent years. This technology will increase the utilization of offshore wind resources, optimize the design and safe operation of wind turbines, increase the efficiency of wind energy conversion, and strengthen China’s large-scale offshore wind turbines. The independent research and development capabilities and the promotion of localization of equipment are of great significance," Shi said.
Based on the challenges brought about by the new development trend of international wind power technology, the National Energy Administration established the first national energy R&D (experimental) centers in December 2009. The National Institute of Engineering Thermophysics established the National Energy Wind Blade Research and Development (experimental). The center, which specializes in research and development of a new generation of wind power technology.
New Blades Bring New Industry Growth Points With the future development trend of the wind power industry, some new types of blades will bring new growth points to the industry.
Such as new wind turbine-specific airfoils, blunt trailing edge blades, bionic blades, low-noise blades, smart blades, etc., such as suitable for China's high wind and sand, low wind speed areas and for the special airfoil under the conditions of anti-typhoon at sea.
“Pecic weather conditions in northern China, such as ice formation, sand dust, insect corpse deposits, and salt erosion, will increase the surface roughness of the fan blades and increase the frictional resistance. This will eventually lead to a reduction in the power generation efficiency of the turbine and a reduction in the fatigue life of the blades. The increase in the flexibility of the scale blade makes the blade often in the large angle of attack separation zone, causing serious stalling, reducing the power generation efficiency and causing fatigue vibration of the blade; in addition, the problem of large-scale blade induced noise can not be ignored. "Shi Kezhong introduced the so-called bionic blade. It is to solve these problems, according to the unique features of some animal and plant epidermis and wings in nature, optimize the design of the blade to solve such problems by optimizing the fluid flow state. He predicted that during the “Thirteenth Five-Year Plan†period, the center will be able to complete the development of bionic blades and realize industrialization.
The study of blunt trailing edge leaves is focused on the regional characteristics of frequent typhoons in the southern coastal areas. In the future, the development of coastal wind power and offshore wind power imposes high requirements on the anti-typhoon performance of the blades. For this purpose, the center adopts a typhoon-based tactics based on the blunt trailing edge blade technology, which leads to increased blade resistance for the blunt trailing edge airfoil. The shortcomings include the development of a series of mechanisms for increasing the drag and drag and the blunt trailing edge airfoil modeling method, and for the development of large-scale offshore wind turbine blades with China's independent intellectual property rights.
At present, one of the technical difficulties of offshore wind power lies in the corrosion resistance of wind turbines. Therefore, the research and development of future leaf materials will focus on solving this problem. In addition to anti-corrosion, these new researches also focus on reducing the weight of the blades and improving economic efficiency. At the same time, the structure of the blades is deformed, low temperature resistant, lightning resistant, salt spray resistant, and dust storm resistant.
“With the rapid development of the wind power industry, the environmental impact caused by the decommissioning of blades is increasing. The adoption of new materials and new processes such as recyclable thermoplastic blade resin matrix is ​​likely to become the hotspot for wind turbine blade research and manufacturing in the future. One", the stone may repeat.
In addition, due to the unstable characteristics of wind energy, with the increasing proportion of wind turbines in the power grid, the impact on the power grid becomes more and more obvious. The smart grid will be an effective solution to the grid-connected generation of renewable energy. Smart blades have also become a direction for future industrial development.
“Intelligent wind turbines put forward high requirements for a series of technologies such as load optimization control technology, simulation methods, wind power prediction technology, detection technology, fault diagnosis and early warning systems for wind turbines, and they are important for the research of a new generation of wind power technologies. One of the directions," Shi said.
The intelligentization of wind turbines is still a work of great economic value. Adopting new load control technology based on advanced sensing, transmission and control technologies (ie, intelligent blade technology) can reduce additional blade loads that damage rotors and other components, reduce blade material requirements, reduce maintenance, and improve wind turbine reliability. At the same time, it can also reduce the load and weight of the transmission system, towers, nacelles and other components to a certain extent, thereby greatly reducing the cost of the fan.
The Institute for Engineering Thermophysics of the Chinese Academy of Sciences was established in 1980. The predecessor of the Institute of Engineering Thermophysics of the Chinese Academy of Sciences was founded in 1956. It is the founder of the ternary flow theory of impeller mechanics, and the founder of engineering thermophysics Professor Wu Zhonghua founded the Power Research Institute of the Chinese Academy of Sciences in 1956.
Xu Jianzhong is the academic leader of the R&D center. He is also an academician of the Chinese Academy of Sciences. He has made achievements in fundamental research and applied research in the aerodynamics of turbomachinery. With him as the representative, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences established a high-level scientific research team in the field of wind energy utilization, which is closely integrated with the industry, and has a team of chief scientists composed of nine senior experts.
In order to break the long-term technical blockade of foreign wind power companies, the institute cooperated with Baoding Development Zone to set up the first company in China that specializes in wind turbine blade R&D. In November 2007, the center put into operation the first 1.5/2.0 MW wind power blade in China.
In October 2009, the 1.5MW 38m blade developed using the design technology of the large-size pre-bent wind-powered wind turbine blade was used for batch production and the on-hook operation was performed at the wind farm of the West Bridge in Chongli, Zhangbei. This type of product is the first 1.5MW wind turbine blade certified by the Certification and Certification Center in China. Its aerodynamic efficiency, noise and other indicators have reached the level of similar products in the world, laying the foundation for the establishment of China's independent intellectual property rights blade design system. .
The series of blades designed to closely match the conditions of China's wind resources has reached an annual capacity of 1,000 blades. “The 42.8m blade aerodynamic efficiency and noise suitable for low wind speed areas have reached the advanced level of similar products in the world. The price of the blade is 10%-15% lower than the import price of similar foreign products. What's more commendable is that this blade is from the beginning. It took only three and a half months from the design to the completion of the hang-up to truly reflect China's speed,†Shi introduced.
In addition, they also cooperated with South Korea's DACC Corporation and Hyosung Company to carry out 2.0MW 43.8m blade gas core design and manufacture of molds, sample production and complete the static and modal testing of the blades, achieving China's independent intellectual property rights The first export of wind power technology.
"This project marks that China's blade manufacturing technology is no longer just a simple introduction of technology, but can be achieved on the premise of independent innovation to achieve wind turbine blade core mold design and manufacturing, blade manufacturing, blade detection technology output," Shi can be introduced.
Prior to this, in order to track international advanced design concepts and development direction, the Institute established the “China-Holland Joint Wind Energy Research Center†together with the Dutch National Energy Center (ECN) in 2007. In the same year, the wind power blades of Hebei Province were jointly built with the Baoding Development Zone. Engineering Center At present, the center has a certain reputation and influence in the industry, and has provided blade design, inspection and technical support services for many domestic blade manufacturers.
In 2010, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences and Huarui Wind Power signed an agreement to jointly build the "Jiangsu Offshore Wind Power Research Institute," and the cooperation between Guodian United Power is also steadily advancing. At present, they are planning to establish the "Cross-Strait Wind Power Research Institute." Cooperation with Dongqi and Guodian United Power is also well under way.
Due to its leading domestic blade technology, the National Energy Administration approved the National Institute of Engineering Thermophysics of the Chinese Academy of Sciences in 2009 to establish a national blade inspection center. The center refers to the detection and operation experience of the United States Renewable Energy Laboratory, the Danish National Wind Energy Research Center and other well-known foreign institutions. The certification system accepts or directly accepts the company's testing requirements and provides testing services. The testing organization shall test the sample delivery products according to the product certification implementation rules and their related specifications and standards. After the inspection is completed, the inspection agency shall submit the inspection report to the certification organization or inspection company. The completion of the center will play an important role in promoting the healthy development of China's wind power industry.
According to reports, during the "12th Five-Year Plan" period, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences will focus on the research and development of new types of blades and related key core technologies with completely independent intellectual property rights, and the organic combination of basic research and the research, production and research system of high-tech R&D. After five years of development, the wind power blade research and development capabilities in China will be at the forefront of the world.
Different countries have different geographical and climatic characteristics, and also bring different requirements to the design of the blades. For example, in China's northern and southern regions, there are low temperatures, high winds, high temperature and humidity in the coastal areas, and more typhoons, and low wind speed in the wind field.
This regionalization requires the development of a series of regionalized technologies such as anti-typhoon blades, low-velocity blades, bionic blades, and low-noise blades. Shi reiterates that the next phase of wind power research in China will be based on the characteristics of Chinese wind resources. Product design and technology development.
In addition, he also pointed out that intelligence is also the trend of wind power technology development in the future. The continuous increase in the size and weight of wind turbine blades makes it more and more difficult to control the wind turbines. Therefore, smart blade technology is also one of the important directions for the research of a new generation of wind power technologies.
In fact, with the rapid development of the wind power industry, offshore wind power plays an important role in a new generation of wind power technology. He also pointed out that we should also pay attention to the new challenges brought about by the development of offshore wind power. At present, onshore wind farm equipment and construction technologies are basically mature. With the depletion of land-based wind energy resources in Europe, the main driving force for the future development of wind energy technology will come from the booming offshore wind power. Offshore wind power imposes higher requirements on the safety, reliability, ease of maintenance, and construction cost control of wind turbines. China has abundant offshore wind resources. With the gradual maturation of offshore wind power technology and the reduction of costs, offshore wind energy will inevitably become an important part of China's future energy structure.
“Floating wind turbines are the focus of R&D in foreign wind power industry in recent years. This technology will increase the utilization of offshore wind resources, optimize the design and safe operation of wind turbines, increase the efficiency of wind energy conversion, and strengthen China’s large-scale offshore wind turbines. The independent research and development capabilities and the promotion of localization of equipment are of great significance," Shi said.
Based on the challenges brought about by the new development trend of international wind power technology, the National Energy Administration established the first national energy R&D (experimental) centers in December 2009. The National Institute of Engineering Thermophysics established the National Energy Wind Blade Research and Development (experimental). The center, which specializes in research and development of a new generation of wind power technology.
New Blades Bring New Industry Growth Points With the future development trend of the wind power industry, some new types of blades will bring new growth points to the industry.
Such as new wind turbine-specific airfoils, blunt trailing edge blades, bionic blades, low-noise blades, smart blades, etc., such as suitable for China's high wind and sand, low wind speed areas and for the special airfoil under the conditions of anti-typhoon at sea.
“Pecic weather conditions in northern China, such as ice formation, sand dust, insect corpse deposits, and salt erosion, will increase the surface roughness of the fan blades and increase the frictional resistance. This will eventually lead to a reduction in the power generation efficiency of the turbine and a reduction in the fatigue life of the blades. The increase in the flexibility of the scale blade makes the blade often in the large angle of attack separation zone, causing serious stalling, reducing the power generation efficiency and causing fatigue vibration of the blade; in addition, the problem of large-scale blade induced noise can not be ignored. "Shi Kezhong introduced the so-called bionic blade. It is to solve these problems, according to the unique features of some animal and plant epidermis and wings in nature, optimize the design of the blade to solve such problems by optimizing the fluid flow state. He predicted that during the “Thirteenth Five-Year Plan†period, the center will be able to complete the development of bionic blades and realize industrialization.
The study of blunt trailing edge leaves is focused on the regional characteristics of frequent typhoons in the southern coastal areas. In the future, the development of coastal wind power and offshore wind power imposes high requirements on the anti-typhoon performance of the blades. For this purpose, the center adopts a typhoon-based tactics based on the blunt trailing edge blade technology, which leads to increased blade resistance for the blunt trailing edge airfoil. The shortcomings include the development of a series of mechanisms for increasing the drag and drag and the blunt trailing edge airfoil modeling method, and for the development of large-scale offshore wind turbine blades with China's independent intellectual property rights.
At present, one of the technical difficulties of offshore wind power lies in the corrosion resistance of wind turbines. Therefore, the research and development of future leaf materials will focus on solving this problem. In addition to anti-corrosion, these new researches also focus on reducing the weight of the blades and improving economic efficiency. At the same time, the structure of the blades is deformed, low temperature resistant, lightning resistant, salt spray resistant, and dust storm resistant.
“With the rapid development of the wind power industry, the environmental impact caused by the decommissioning of blades is increasing. The adoption of new materials and new processes such as recyclable thermoplastic blade resin matrix is ​​likely to become the hotspot for wind turbine blade research and manufacturing in the future. One", the stone may repeat.
In addition, due to the unstable characteristics of wind energy, with the increasing proportion of wind turbines in the power grid, the impact on the power grid becomes more and more obvious. The smart grid will be an effective solution to the grid-connected generation of renewable energy. Smart blades have also become a direction for future industrial development.
“Intelligent wind turbines put forward high requirements for a series of technologies such as load optimization control technology, simulation methods, wind power prediction technology, detection technology, fault diagnosis and early warning systems for wind turbines, and they are important for the research of a new generation of wind power technologies. One of the directions," Shi said.
The intelligentization of wind turbines is still a work of great economic value. Adopting new load control technology based on advanced sensing, transmission and control technologies (ie, intelligent blade technology) can reduce additional blade loads that damage rotors and other components, reduce blade material requirements, reduce maintenance, and improve wind turbine reliability. At the same time, it can also reduce the load and weight of the transmission system, towers, nacelles and other components to a certain extent, thereby greatly reducing the cost of the fan.
The Institute for Engineering Thermophysics of the Chinese Academy of Sciences was established in 1980. The predecessor of the Institute of Engineering Thermophysics of the Chinese Academy of Sciences was founded in 1956. It is the founder of the ternary flow theory of impeller mechanics, and the founder of engineering thermophysics Professor Wu Zhonghua founded the Power Research Institute of the Chinese Academy of Sciences in 1956.
Xu Jianzhong is the academic leader of the R&D center. He is also an academician of the Chinese Academy of Sciences. He has made achievements in fundamental research and applied research in the aerodynamics of turbomachinery. With him as the representative, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences established a high-level scientific research team in the field of wind energy utilization, which is closely integrated with the industry, and has a team of chief scientists composed of nine senior experts.
In order to break the long-term technical blockade of foreign wind power companies, the institute cooperated with Baoding Development Zone to set up the first company in China that specializes in wind turbine blade R&D. In November 2007, the center put into operation the first 1.5/2.0 MW wind power blade in China.
In October 2009, the 1.5MW 38m blade developed using the design technology of the large-size pre-bent wind-powered wind turbine blade was used for batch production and the on-hook operation was performed at the wind farm of the West Bridge in Chongli, Zhangbei. This type of product is the first 1.5MW wind turbine blade certified by the Certification and Certification Center in China. Its aerodynamic efficiency, noise and other indicators have reached the level of similar products in the world, laying the foundation for the establishment of China's independent intellectual property rights blade design system. .
The series of blades designed to closely match the conditions of China's wind resources has reached an annual capacity of 1,000 blades. “The 42.8m blade aerodynamic efficiency and noise suitable for low wind speed areas have reached the advanced level of similar products in the world. The price of the blade is 10%-15% lower than the import price of similar foreign products. What's more commendable is that this blade is from the beginning. It took only three and a half months from the design to the completion of the hang-up to truly reflect China's speed,†Shi introduced.
In addition, they also cooperated with South Korea's DACC Corporation and Hyosung Company to carry out 2.0MW 43.8m blade gas core design and manufacture of molds, sample production and complete the static and modal testing of the blades, achieving China's independent intellectual property rights The first export of wind power technology.
"This project marks that China's blade manufacturing technology is no longer just a simple introduction of technology, but can be achieved on the premise of independent innovation to achieve wind turbine blade core mold design and manufacturing, blade manufacturing, blade detection technology output," Shi can be introduced.
Prior to this, in order to track international advanced design concepts and development direction, the Institute established the “China-Holland Joint Wind Energy Research Center†together with the Dutch National Energy Center (ECN) in 2007. In the same year, the wind power blades of Hebei Province were jointly built with the Baoding Development Zone. Engineering Center At present, the center has a certain reputation and influence in the industry, and has provided blade design, inspection and technical support services for many domestic blade manufacturers.
In 2010, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences and Huarui Wind Power signed an agreement to jointly build the "Jiangsu Offshore Wind Power Research Institute," and the cooperation between Guodian United Power is also steadily advancing. At present, they are planning to establish the "Cross-Strait Wind Power Research Institute." Cooperation with Dongqi and Guodian United Power is also well under way.
Due to its leading domestic blade technology, the National Energy Administration approved the National Institute of Engineering Thermophysics of the Chinese Academy of Sciences in 2009 to establish a national blade inspection center. The center refers to the detection and operation experience of the United States Renewable Energy Laboratory, the Danish National Wind Energy Research Center and other well-known foreign institutions. The certification system accepts or directly accepts the company's testing requirements and provides testing services. The testing organization shall test the sample delivery products according to the product certification implementation rules and their related specifications and standards. After the inspection is completed, the inspection agency shall submit the inspection report to the certification organization or inspection company. The completion of the center will play an important role in promoting the healthy development of China's wind power industry.
According to reports, during the "12th Five-Year Plan" period, the Institute of Engineering Thermophysics of the Chinese Academy of Sciences will focus on the research and development of new types of blades and related key core technologies with completely independent intellectual property rights, and the organic combination of basic research and the research, production and research system of high-tech R&D. After five years of development, the wind power blade research and development capabilities in China will be at the forefront of the world.
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