Ultra High Voltage - Key to Cracking the Grid Bottleneck
In the first decade of the 21st century, China’s electric power construction was faster than ever before, and the installed capacity of electric power increased rapidly from 320 million kilowatts in 2000 to the current 800 million kilowatts. In particular, during the "11th Five-Year Plan" period, China's newly installed power capacity reached 430 million kilowatts, completed 5 years of total installed capacity of electric power in the past 50 years, and the annual new installed capacity exceeds that of the UK.
However, at the same time as the rapid development of power supply construction, there has been no fundamental solution to the long-standing problem of heavy-power construction and light-grid construction in the power industry. Due to the lag in grid construction, a series of new problems and contradictions have emerged. For example, the speeding up of the construction of thermal power plants fuels the bottleneck of transportation bottlenecks that were already intense. By the peak of electricity use, many power plants in the country are in urgent need of electricity coal stocks, and the “emergency of coal combustion†is almost normal. In the southwest, hydropower and wind power in the northwest have been obstructed by delivery, and they have to abandon the water and discard the wind. The development of clean renewable energy is hindered... This year is the first year of the “Twelfth Five-Year Plan†and the “Eleventh Five-Year†period has been exposed. Will these problems be fundamentally resolved in the 12th Five-Year Plan? The relevant power experts told us that with the acceleration of the construction of UHV power grids, these difficulties may become history.
UHV construction "Twelfth Five-Year Plan" or will accelerate the breaking of ice 2011 New Year just passed, on January 6, the National Development and Reform Commission approved the expansion of the UHV AC pilot demonstration project expansion project. The project is planned to be put into operation during the year. After the expansion, the capacity will be expanded to 5 million kilowatts. This expansion project has become the starting project for China’s UHV construction during the “Twelfth Five-Year Plan†period.
Just 20 days apart, on January 26, the State Grid Corporation of China announced that it would spare no effort to advance the ±1100 kV UHVDC research and that a demonstration project would be completed within five years, thus providing support for large-scale energy bases with a distance of more than 2,400 kilometers.
In the first year of the Twelfth Five-Year Plan, UHV construction kicked off in full swing.
According to the forecast of related departments, during the “Twelfth Five-Year Plan†period, China’s power demand will continue to maintain a rapid growth trend, with an average annual growth rate of more than 8%, and an average annual increase in installed power capacity of nearly 100 million kilowatts. By the end of the "Twelfth Five-Year Plan," China's electric power installation is expected to reach about 1.44 billion kilowatts. In order to ensure energy demand, China will also accelerate the construction of coal and electricity bases such as Shanxi, Shaanxi, Ningxia, Mengxin, Jinsha River, Yalong River, and Dadu River, as well as Xinjiang, Gansu, Inner Mongolia, Jilin, Hebei, and Jiangsu. Tens of kilowatts of wind power bases. By 2015, the scale of the above coal, electricity, hydropower, and wind power delivery will reach 150 million kilowatts, 50 million kilowatts, and 60 million kilowatts, respectively.
Such large-capacity and long-distance transmission across regions will have to solve bottlenecks in the transmission of power grids, and the development of UHV will become the top priority for the construction of the “12th Five-Year Plan†power grid.
In the “Twelfth Five-Year Planâ€, the State Grid Corporation of China proposed that in the future, China will build “three vertical and three horizontal†UHV backbone grids and 13 DC transmission projects linking large-scale energy bases and major load centers (including 10 UHV DCs). ), Form a large-scale "West Power Transmission to the East," "Northern Power Transmission," the energy allocation pattern. By 2015, a strong smart grid with the characteristics of informatization, automation, and interaction will be built with the UHV power grid as the backbone grid and coordinated development of all levels of power grids. The “Three Chinas†(North China, Central China, East China), and Northwest China will be formed. The three northeastern synchronous power grids have enabled the State Grid to comprehensively increase its resource allocation capacity, economic operating efficiency, safety level, technological level, and intelligence level.
In the "12th Five-Year Plan", China may fully usher in the UHV era.
Why is UHV?
The so-called UHV power grid is a transmission network that communicates voltage levels of 1,000 kilovolts and plus or minus 800 kilovolts and above. Its greatest feature is its ability to transmit power over long distances, large capacity, and low losses. It is estimated that the transmission capacity of a 1000 kV UHV transmission line exceeds 5 million kilowatts, which is close to 5 times that of a 500 kV UHV AC transmission line. The transmission capacity of ± 800 kV DC UHV reaches 7 million kilowatts, which is 2.4 times the transmission capacity of ± 500 kV UHV DC lines.
The reason why UHV was chosen as the key technology to solve the bottleneck of China's power grid is to make decisions based on China's special national conditions.
According to Bai Jianhua, deputy chief economist of the State Grid Energy Research Institute and director of the Institute of Energy Strategy and Planning, 76% of China’s coal resources are located in the north and northwest; 80% of hydropower resources are distributed in the southwest; most of the land Wind energy and solar energy resources are distributed in the northwest. At the same time, over 70% of energy demand is concentrated in the eastern and central regions. The distance between the energy base and the load center is between 1000 and 3000 kilometers.
Such a layout provides two options: either building a power station in the load center area or sending power after building a power station in the energy center area.
The large-scale development of power supply in the load center area is obviously subject to various constraints. Such as coal transportation problems, environmental capacity issues and so on. Moreover, the construction of thermal power can also be transported by coal, and because hydropower and wind power cannot transport water and wind like coal, it cannot be realized. On the one hand, it is not possible to construct power points on a large scale, and while watching the valuable clean energy such as hydropower and wind energy, it is evident that the idea of ​​large-scale development of power supply in load centers is not feasible.
Therefore, building power supplies in the western and northern regions where energy resources are abundant, and then sending power to the center of compliance is the only choice.
So can the existing grid achieve such large power handling? Power grid experts tell us that it is impossible. Because the current 500 kV EHV line not only has a small power transmission capacity, but it is mainly unable to achieve long-distance transmission.
Therefore, power grid experts pointed out that building an ultra-high voltage power grid capable of large-capacity, long-distance, low-loss power transmission becomes the top priority for the “Twelfth Five-Year Plan†power grid construction, and it is the best choice.
Xue Yusheng, an academician of the Chinese Academy of Engineering, believes that UHV not only has the ability to transfer energy over long distances and large volumes, but also eases transportation pressure, improves economic efficiency, and promotes clean energy development.
First of all, from the perspective of optimizing resources allocation, as China's energy strategy moves westward, the distance between large-scale energy bases and energy consumption centers will be further and longer, and the scale of energy transmission will also increase. On the basis of traditional methods of transportation such as railways, highways, shipping, and pipelines, improving the transportation capacity of the power grid is also a choice to ease the pressure on transportation. Taking the 1,000 kV high-voltage demonstration project that has been put into operation for example, at present, it can deliver 2 million kilowatts per day, and it can reach 5 million kilowatts after transformation. This is equivalent to the daily transportation of 25,000 to 60,000 tons of raw coal from Shanxi to Hubei. Hubei media said that this is equivalent to sending a Hubei Gezhouba Power Station to Hubei.
Looking at the economic benefits, at present, the price of thermal coal in the western and northern regions is 200 yuan/ton of standard coal. The coal is loaded locally, transported by road and rail to Qinhuangdao Port, and then transported by sea and road to East China. The price of thermal coal is increased to more than 1,000 yuan/ton of standard coal. After conversion, the fuel cost per kilowatt-hour is only around 0.3 yuan. In the coal-producing areas of Hang Hau Power Station, the fuel cost is only RMB 0.09/kWh. The power of the Hangkou Power Station was transported to the Central and Eastern Load Center through UHV. After the cost of the transmission link was removed, the price of electricity to the grid was still lower than the average on-grid tariff of the local coal power of 0.06-0.13 yuan/kWh.
UHV is even more necessary for the development of clean energy. Only UHV can solve the problem of large-scale clean energy generation. Some time ago, the issue of “sun drying†in wind power in Inner Mongolia was widely concerned. In fact, China's wind power is mainly concentrated in the "Three North" region, and the local consumption space is very limited. The further development of wind power objectively needs to expand the range of wind power consumption, large wind power must be integrated into the large power grid, and a strong large power grid can significantly increase the capacity of wind power consumption. UHV power grid will constitute a large-capacity, long-distance energy transmission channel in China. According to calculations, if wind power is only consumed in the province, the scale of wind power that can be developed in the country by 2020 is about 50 million kilowatts. Through the use of UHV cross-area networked transmission to expand the absorption capacity of clean energy, the national wind power development scale can reach more than 100 million kilowatts.
Can UHV be built?
Despite all the above benefits, the UHV is, after all, a new technology for the power system, and there is no commercial operation experience in the world. It has also been defined by the International Conference on Large-scale Grids as "the technology to be matured". Moreover, the higher the voltage level of the power grid, the greater the coverage area and the greater the potential safety hazard. Long-distance power grids are prone to natural disasters such as typhoons, rainstorms, and lightning strikes. So there is no guarantee of UHV security? Faced with many difficulties at home and abroad with no mature technology and no ready-made equipment, can we build a UHV power grid?
Xue Shengsheng, an academician of the Chinese Academy of Engineering, told us that after the successful operation and smooth operation of the 1,000 kV VJ-SZ demonstration project in Jindongnan-Nanyang-Jingmen and the ±800 kV DC demonstration project in Shanghai, we are fully confident that Ability to build a good UHV.
According to the introduction of the State Grid Corporation of China, the two large UHV demonstration projects have widely adopted new technologies, new materials and new processes, and successfully solved the problems of large-span construction, large-scale transportation, and centralized installation and debugging of a large number of new equipment. They only used 28 months respectively. It took 30 months to complete the construction task and successfully put it into operation once. Up to now, 853 days and 212 days of safe and stable operation have been achieved respectively, and the project's expected goals of safety, quality, progress, and environmental protection have all been realized. This has provided valuable experience for the large-scale construction of UHV in the future.
For example, the security of the power grid, Sun Wei, director of the UHV Construction Department of the State Grid Corporation of China, stressed that “the safety of UHV is guaranteed. The UHV AC transmission demonstration project was put into operation for more than two years and achieved bi-directional, full-voltage, and large-capacity transmission. It has been subjected to severe conditions such as thunderstorms, high winds, high temperatures, and severe cold. The actual measured transmission loss rate was 1.7%, which is about 1/3 of that of a 500-kV project. The performance indicators fully meet the design requirements, said Lu Qiang, an academician of the Chinese Academy of Sciences. Assuming that a large interference event occurs on a UHV line, can a large AC synchronous system maintain security and stability? We conducted simulation experiments in five or six hundred situations. The answer is: safety and stability are guaranteed, and there is a series of innovative technologies to ensure.
Regarding the lack of ready-made technologies, equipment and standards at home and abroad, the State Grid Corporation of China regards developing UHV as a major scientific and technological innovation project. At the beginning of its conception and comprehensive start-up, the company has invested huge sums to build a world-class UHV AC. , DC, high altitude, engineering mechanics four experimental bases and large power grid simulation, DC package design two R & D centers, formed a fully functional, comprehensive indicators in the world leading level of large-scale power grid experimental research system. During the past few years, State Grid Corporation of China has completed 310 key technical studies on UHV projects, solving a number of world problems such as overvoltage and insulation coordination, external insulation design, electromagnetic environment control, system integration, and large-scale power grid safe operation control. Gradually mastered the key core technologies of UHV transmission, and has been successfully applied in experimental projects.
The UHV construction has a more obvious driving role in the domestic equipment manufacturing industry. The equipment used by the three major UHV experimental projects in the country is almost entirely supplied by domestic companies. The localization rate of the project reaches approximately 95%, and the localization rate of equipment reaches approximately 91%. Through experimental projects, domestic equipment manufacturing companies have been tempered, and their R&D capabilities have greatly increased. Nantong Shenma Power Technology Co., Ltd., for example, succeeded in overcoming the global challenges of UHV insulators. Ma Bin, chairman of the company, said that the performance of the world's first ultra high voltage 1000 kV hollow composite insulator, which we invested nearly 100 million yuan, has reached the international advanced level, and the price is only 1/3 of that of foreign products.
The relevant personnel of the State Grid Corporation of China told reporters with confidence that with the large-scale construction of UHV projects, the major equipment and material manufacturing technologies have gradually matured, the construction technology has been continuously improved, the scale effect has become prominent, the cost level will further decline, and the technology economy will be further reduced. Will be more fully reflected.
The success of China’s UHV has led to the development of UHV technology in the world. The two international conferences on UHV transmission technologies held in 2006 and 2009 have enabled the world to understand the development of UHV in China. At present, India, Brazil, the United States, Russia and other countries are actively studying and promoting UHV transmission, and actively seek cooperation with the State Grid Corporation. U.S. Secretary of Energy Zhu Yuwen views China's UHV innovation as a challenge to U.S. leadership in science and technology. At present, the prelude to the development of UHV power grids has been played, and the spring of UHV construction has arrived. Some experts believe that we should face up to all kinds of difficulties and strive to make this advanced technology benefit the country and the people as soon as possible.
However, at the same time as the rapid development of power supply construction, there has been no fundamental solution to the long-standing problem of heavy-power construction and light-grid construction in the power industry. Due to the lag in grid construction, a series of new problems and contradictions have emerged. For example, the speeding up of the construction of thermal power plants fuels the bottleneck of transportation bottlenecks that were already intense. By the peak of electricity use, many power plants in the country are in urgent need of electricity coal stocks, and the “emergency of coal combustion†is almost normal. In the southwest, hydropower and wind power in the northwest have been obstructed by delivery, and they have to abandon the water and discard the wind. The development of clean renewable energy is hindered... This year is the first year of the “Twelfth Five-Year Plan†and the “Eleventh Five-Year†period has been exposed. Will these problems be fundamentally resolved in the 12th Five-Year Plan? The relevant power experts told us that with the acceleration of the construction of UHV power grids, these difficulties may become history.
UHV construction "Twelfth Five-Year Plan" or will accelerate the breaking of ice 2011 New Year just passed, on January 6, the National Development and Reform Commission approved the expansion of the UHV AC pilot demonstration project expansion project. The project is planned to be put into operation during the year. After the expansion, the capacity will be expanded to 5 million kilowatts. This expansion project has become the starting project for China’s UHV construction during the “Twelfth Five-Year Plan†period.
Just 20 days apart, on January 26, the State Grid Corporation of China announced that it would spare no effort to advance the ±1100 kV UHVDC research and that a demonstration project would be completed within five years, thus providing support for large-scale energy bases with a distance of more than 2,400 kilometers.
In the first year of the Twelfth Five-Year Plan, UHV construction kicked off in full swing.
According to the forecast of related departments, during the “Twelfth Five-Year Plan†period, China’s power demand will continue to maintain a rapid growth trend, with an average annual growth rate of more than 8%, and an average annual increase in installed power capacity of nearly 100 million kilowatts. By the end of the "Twelfth Five-Year Plan," China's electric power installation is expected to reach about 1.44 billion kilowatts. In order to ensure energy demand, China will also accelerate the construction of coal and electricity bases such as Shanxi, Shaanxi, Ningxia, Mengxin, Jinsha River, Yalong River, and Dadu River, as well as Xinjiang, Gansu, Inner Mongolia, Jilin, Hebei, and Jiangsu. Tens of kilowatts of wind power bases. By 2015, the scale of the above coal, electricity, hydropower, and wind power delivery will reach 150 million kilowatts, 50 million kilowatts, and 60 million kilowatts, respectively.
Such large-capacity and long-distance transmission across regions will have to solve bottlenecks in the transmission of power grids, and the development of UHV will become the top priority for the construction of the “12th Five-Year Plan†power grid.
In the “Twelfth Five-Year Planâ€, the State Grid Corporation of China proposed that in the future, China will build “three vertical and three horizontal†UHV backbone grids and 13 DC transmission projects linking large-scale energy bases and major load centers (including 10 UHV DCs). ), Form a large-scale "West Power Transmission to the East," "Northern Power Transmission," the energy allocation pattern. By 2015, a strong smart grid with the characteristics of informatization, automation, and interaction will be built with the UHV power grid as the backbone grid and coordinated development of all levels of power grids. The “Three Chinas†(North China, Central China, East China), and Northwest China will be formed. The three northeastern synchronous power grids have enabled the State Grid to comprehensively increase its resource allocation capacity, economic operating efficiency, safety level, technological level, and intelligence level.
In the "12th Five-Year Plan", China may fully usher in the UHV era.
Why is UHV?
The so-called UHV power grid is a transmission network that communicates voltage levels of 1,000 kilovolts and plus or minus 800 kilovolts and above. Its greatest feature is its ability to transmit power over long distances, large capacity, and low losses. It is estimated that the transmission capacity of a 1000 kV UHV transmission line exceeds 5 million kilowatts, which is close to 5 times that of a 500 kV UHV AC transmission line. The transmission capacity of ± 800 kV DC UHV reaches 7 million kilowatts, which is 2.4 times the transmission capacity of ± 500 kV UHV DC lines.
The reason why UHV was chosen as the key technology to solve the bottleneck of China's power grid is to make decisions based on China's special national conditions.
According to Bai Jianhua, deputy chief economist of the State Grid Energy Research Institute and director of the Institute of Energy Strategy and Planning, 76% of China’s coal resources are located in the north and northwest; 80% of hydropower resources are distributed in the southwest; most of the land Wind energy and solar energy resources are distributed in the northwest. At the same time, over 70% of energy demand is concentrated in the eastern and central regions. The distance between the energy base and the load center is between 1000 and 3000 kilometers.
Such a layout provides two options: either building a power station in the load center area or sending power after building a power station in the energy center area.
The large-scale development of power supply in the load center area is obviously subject to various constraints. Such as coal transportation problems, environmental capacity issues and so on. Moreover, the construction of thermal power can also be transported by coal, and because hydropower and wind power cannot transport water and wind like coal, it cannot be realized. On the one hand, it is not possible to construct power points on a large scale, and while watching the valuable clean energy such as hydropower and wind energy, it is evident that the idea of ​​large-scale development of power supply in load centers is not feasible.
Therefore, building power supplies in the western and northern regions where energy resources are abundant, and then sending power to the center of compliance is the only choice.
So can the existing grid achieve such large power handling? Power grid experts tell us that it is impossible. Because the current 500 kV EHV line not only has a small power transmission capacity, but it is mainly unable to achieve long-distance transmission.
Therefore, power grid experts pointed out that building an ultra-high voltage power grid capable of large-capacity, long-distance, low-loss power transmission becomes the top priority for the “Twelfth Five-Year Plan†power grid construction, and it is the best choice.
Xue Yusheng, an academician of the Chinese Academy of Engineering, believes that UHV not only has the ability to transfer energy over long distances and large volumes, but also eases transportation pressure, improves economic efficiency, and promotes clean energy development.
First of all, from the perspective of optimizing resources allocation, as China's energy strategy moves westward, the distance between large-scale energy bases and energy consumption centers will be further and longer, and the scale of energy transmission will also increase. On the basis of traditional methods of transportation such as railways, highways, shipping, and pipelines, improving the transportation capacity of the power grid is also a choice to ease the pressure on transportation. Taking the 1,000 kV high-voltage demonstration project that has been put into operation for example, at present, it can deliver 2 million kilowatts per day, and it can reach 5 million kilowatts after transformation. This is equivalent to the daily transportation of 25,000 to 60,000 tons of raw coal from Shanxi to Hubei. Hubei media said that this is equivalent to sending a Hubei Gezhouba Power Station to Hubei.
Looking at the economic benefits, at present, the price of thermal coal in the western and northern regions is 200 yuan/ton of standard coal. The coal is loaded locally, transported by road and rail to Qinhuangdao Port, and then transported by sea and road to East China. The price of thermal coal is increased to more than 1,000 yuan/ton of standard coal. After conversion, the fuel cost per kilowatt-hour is only around 0.3 yuan. In the coal-producing areas of Hang Hau Power Station, the fuel cost is only RMB 0.09/kWh. The power of the Hangkou Power Station was transported to the Central and Eastern Load Center through UHV. After the cost of the transmission link was removed, the price of electricity to the grid was still lower than the average on-grid tariff of the local coal power of 0.06-0.13 yuan/kWh.
UHV is even more necessary for the development of clean energy. Only UHV can solve the problem of large-scale clean energy generation. Some time ago, the issue of “sun drying†in wind power in Inner Mongolia was widely concerned. In fact, China's wind power is mainly concentrated in the "Three North" region, and the local consumption space is very limited. The further development of wind power objectively needs to expand the range of wind power consumption, large wind power must be integrated into the large power grid, and a strong large power grid can significantly increase the capacity of wind power consumption. UHV power grid will constitute a large-capacity, long-distance energy transmission channel in China. According to calculations, if wind power is only consumed in the province, the scale of wind power that can be developed in the country by 2020 is about 50 million kilowatts. Through the use of UHV cross-area networked transmission to expand the absorption capacity of clean energy, the national wind power development scale can reach more than 100 million kilowatts.
Can UHV be built?
Despite all the above benefits, the UHV is, after all, a new technology for the power system, and there is no commercial operation experience in the world. It has also been defined by the International Conference on Large-scale Grids as "the technology to be matured". Moreover, the higher the voltage level of the power grid, the greater the coverage area and the greater the potential safety hazard. Long-distance power grids are prone to natural disasters such as typhoons, rainstorms, and lightning strikes. So there is no guarantee of UHV security? Faced with many difficulties at home and abroad with no mature technology and no ready-made equipment, can we build a UHV power grid?
Xue Shengsheng, an academician of the Chinese Academy of Engineering, told us that after the successful operation and smooth operation of the 1,000 kV VJ-SZ demonstration project in Jindongnan-Nanyang-Jingmen and the ±800 kV DC demonstration project in Shanghai, we are fully confident that Ability to build a good UHV.
According to the introduction of the State Grid Corporation of China, the two large UHV demonstration projects have widely adopted new technologies, new materials and new processes, and successfully solved the problems of large-span construction, large-scale transportation, and centralized installation and debugging of a large number of new equipment. They only used 28 months respectively. It took 30 months to complete the construction task and successfully put it into operation once. Up to now, 853 days and 212 days of safe and stable operation have been achieved respectively, and the project's expected goals of safety, quality, progress, and environmental protection have all been realized. This has provided valuable experience for the large-scale construction of UHV in the future.
For example, the security of the power grid, Sun Wei, director of the UHV Construction Department of the State Grid Corporation of China, stressed that “the safety of UHV is guaranteed. The UHV AC transmission demonstration project was put into operation for more than two years and achieved bi-directional, full-voltage, and large-capacity transmission. It has been subjected to severe conditions such as thunderstorms, high winds, high temperatures, and severe cold. The actual measured transmission loss rate was 1.7%, which is about 1/3 of that of a 500-kV project. The performance indicators fully meet the design requirements, said Lu Qiang, an academician of the Chinese Academy of Sciences. Assuming that a large interference event occurs on a UHV line, can a large AC synchronous system maintain security and stability? We conducted simulation experiments in five or six hundred situations. The answer is: safety and stability are guaranteed, and there is a series of innovative technologies to ensure.
Regarding the lack of ready-made technologies, equipment and standards at home and abroad, the State Grid Corporation of China regards developing UHV as a major scientific and technological innovation project. At the beginning of its conception and comprehensive start-up, the company has invested huge sums to build a world-class UHV AC. , DC, high altitude, engineering mechanics four experimental bases and large power grid simulation, DC package design two R & D centers, formed a fully functional, comprehensive indicators in the world leading level of large-scale power grid experimental research system. During the past few years, State Grid Corporation of China has completed 310 key technical studies on UHV projects, solving a number of world problems such as overvoltage and insulation coordination, external insulation design, electromagnetic environment control, system integration, and large-scale power grid safe operation control. Gradually mastered the key core technologies of UHV transmission, and has been successfully applied in experimental projects.
The UHV construction has a more obvious driving role in the domestic equipment manufacturing industry. The equipment used by the three major UHV experimental projects in the country is almost entirely supplied by domestic companies. The localization rate of the project reaches approximately 95%, and the localization rate of equipment reaches approximately 91%. Through experimental projects, domestic equipment manufacturing companies have been tempered, and their R&D capabilities have greatly increased. Nantong Shenma Power Technology Co., Ltd., for example, succeeded in overcoming the global challenges of UHV insulators. Ma Bin, chairman of the company, said that the performance of the world's first ultra high voltage 1000 kV hollow composite insulator, which we invested nearly 100 million yuan, has reached the international advanced level, and the price is only 1/3 of that of foreign products.
The relevant personnel of the State Grid Corporation of China told reporters with confidence that with the large-scale construction of UHV projects, the major equipment and material manufacturing technologies have gradually matured, the construction technology has been continuously improved, the scale effect has become prominent, the cost level will further decline, and the technology economy will be further reduced. Will be more fully reflected.
The success of China’s UHV has led to the development of UHV technology in the world. The two international conferences on UHV transmission technologies held in 2006 and 2009 have enabled the world to understand the development of UHV in China. At present, India, Brazil, the United States, Russia and other countries are actively studying and promoting UHV transmission, and actively seek cooperation with the State Grid Corporation. U.S. Secretary of Energy Zhu Yuwen views China's UHV innovation as a challenge to U.S. leadership in science and technology. At present, the prelude to the development of UHV power grids has been played, and the spring of UHV construction has arrived. Some experts believe that we should face up to all kinds of difficulties and strive to make this advanced technology benefit the country and the people as soon as possible.
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