Zhongtian Technology Wire: Serving UHV

UHV transmission is called "electric highway." Zhongtian Technology Co., Ltd. and its Shanghai Zhongtian Aluminum Wire Co., Ltd. have recently passed the certification of the six full-series of large-section conductors that will play a huge role in the “electricity highway”. This is a review consensus formed by industry experts.

Cracking the haze

Who will deal with the "horrible haze" than SARS? It has become a subject of great concern to the people in the development of a harmonious society.

Experts pointed out that the construction of UHV transmission channels can play a positive role in mitigating the haze of the Yangtze River Delta, the Pearl River Delta, Beijing-Tianjin-Hebei, and the Bohai Rim. For example, in the Beijing-Tianjin-Hebei region, the installed capacity is about 60 million kilowatts. Through one UHV DC or two UHV exchanges, the power can be transferred from 8 million to 10 million kilowatts, which can replace more than 10% of the local installed capacity. In order to transfer more than 10% of local energy production emissions, the environmental capacity will be balanced in a wider range. This has already surpassed the environmental limits for environmental protection capacity. The above-mentioned haze management in developed regions will play a significant role in delivering carbon emissions.

Zhongtian Technology has compiled the "Corporate Social Responsibility Report" among the first private manufacturing companies in the country. Xue Jiping, chairman of the company, stated that the company's operations must not only pursue good economic benefits, but also take into account social benefits. It is incumbent upon the people to develop products that serve the UHV grid to help control haze.

On March 29, 2014, the China Electric Power Association organized experts to appraise the six major categories of 1250mm2 large-section, energy-saving wire products provided by Zhongtian Science and Technology Co., Ltd. and Shanghai Zhongtian Aluminum Wire Co., Ltd. Experts agreed that Zhongtian provided reliable technical support for the application of DC projects in cross-regional power grids. The new product is the first research and development in China, and its comprehensive technical performance has reached the international advanced level, which has made new contributions to China's power grid to improve its transportation capacity.

Ju Weiren, director of the Zhongtian Science and Technology Institute of Leads and Metals, said that the products passed this certification have met the requirements for large-capacity transmission of UHV AC and DC power. Large section: The 1250 series is the largest UHVDC power transmission wire in China; the 1250 series wire twisted wire is a special product not used at home and abroad; more energy-saving: ACSR, steel core aluminum The conductivity of stranded wire, aluminum alloy aluminum-cored aluminum stranded wire, and steel core medium-strength aluminum alloy stranded wire has been improved on the basis of the original standard; the full range: 1250mm2 series products have achieved full coverage of the application range, ie, they have met the general line requirements. Requirements, but also in the heavy ice area 30mm-50mm use.

Zhongtian Technology is one of the experimental demonstration units of China's UHV power grid construction equipment. Over the years, a number of scientific research achievements have won provincial recognition and awards. In September 2005, China's first 750kV transmission and transformation project was formally put into operation. With the completion of the 750kV power transmission project in East-Silver-Yinchuan East of Lanzhou and the delivery of the Laxiwa hydropower station in Yellow River in Qinghai, a 750kV transmission project in Northwest China was gradually formed. Transformer backbone grid. In January 2009, 1000kV Jindongnan-Nanyang-Jingmen UHV AC pilot demonstration project was commissioned to realize the cross-regional networking of UHV in Central and North China. In 2010, Xiangjiaba-Shanghai ±800kV UHVDC power transmission project and Yunnan-Guangdong ±800kV UHVDC power transmission project were completed. In 2012, Jinping-Sulan ±800kV UHVDC power transmission project was completed. In 2014, the Hami South-Zhengzhou ±800kV UHVDC power transmission project was completed. At present, Xiluodu-Zhejiang Jinhua ±800kV UHV DC transmission project is under construction. As of February 2014, the UHV transmission pattern of “two routes and three lines” has been formed, and six synchronous networks of North China-Central China Power Grid, East China Power Grid, Northeast China Power Grid, Northwest Power Grid, Southern Power Grid and Tibet Power Grid have been formed. In addition to the national network outside Taiwan. Inter-provincial trans-regional power transmission increased from 132.6 billion kWh in 2003 to 694 billion kWh in 2012. At the same time as the optimization of the allocation of large-scale power grid resources, the ability of the power grid to support each other and support each other has increased significantly. In the construction of the aforementioned major projects, Zhongtian Science and Technology has participated in more than 90%.

Relevant data show that it is expected that by 2015 China will build a "two vertical and two horizontal" UHV grid and seven UHV DC projects; by 2017, it will build a "three vertical and three horizontal" grid and 13 UHVDC projects; In 2020, a “five vertical and five horizontal” grid and 27 UHV DC projects will be built to connect various large-scale energy bases and major load centers, and form a large-scale energy distribution pattern from West to East and North to South.

You Wei Ren said that the Zhongtian launch of the existing State Grid Corporation's research group requested the development of products, as well as Zhongtian to meet the market demand for independent research and development of new products launched. The mission of Zhongtian to service UHV construction is very heavy and it needs continuous innovation.

Meet the "Ultra High Voltage" Three Demands

The conductors are the key components of overhead transmission lines, and their inputs occupy a large proportion in the construction of overhead transmission lines and have a decisive significance for the economical efficiency of energy transmission. In addition to meeting the requirements for energy transmission, the selection of conductors for UHV transmission lines must meet the three major demands of transmission safety, advanced technology, and ecological protection. Lu Wei, general manager of Zhongtian Technology Co., Ltd. stated that Zhongtian products fully implemented these three requirements.

Zhongtian full range of conductors meet the safety and reliability requirements of UHV transmission. As the cross-regional transmission must have long-distance requirements, at the same time, the terrain in China is complex and the climate is variable. Products must adapt to various environmental conditions. On the one hand, the line needs to meet the capacity safety margin, and on the other hand, it needs to meet the strength safety margin. Lu Wei said that the large cross-section 1250mm2 series of steel-cored aluminum wire JL1/G2A-1250/100, steel core high-strength aluminum alloy stranded wire JLHA1/G2A-1250/100, aluminum alloy aluminum core wire JL1X1/ LHA1-800/550, steel cores with medium strength aluminum alloy strands JLHA4/G2A-1250/100, and steel core stranded aluminum strands JL1X1/G3A-1250/70 are the largest cross-sections used in domestic UHVDC transmissions. Conductors, single wire current carrying capacity of more than 1700A, compared to the existing 1000mm2 series of wire increased by about 15%, to improve the transmission capacity of the line margin, to meet the various wire environment requirements of wire selection. Lu Wei said that the use of large-section 1250mm2 wire, but also to strengthen the mechanical strength of the wire margin, especially in large rivers, mountains and lakes and other regions need to use higher strength wire. The large section 1250mm2 steel core high-strength aluminum alloy stranded wire JLHA1/G2A-1250/100 developed by Zhongtian Technology is 58.7% stronger than steel-cored aluminum stranded wire and is suitable for large-range, high drop, and long-distance transmission. Has a high safety margin.

The conductivity of large cross-section conductors in Zhongtian can meet the electrical performance requirements of UHV lines. For UHVDC transmission lines, the transmission current is large and the power loss is considerable. Therefore, in the selection of UHVDC transmission line conductors, full consideration should be given to the effects of power loss. Zhongtian Technology Chief Engineer Professor Xie Shuhong said that the large conductors of ZTT have been developed. Among them, the conductivity of aluminum conductors of ACSR has been increased from 61% IACS to 61.5% IACS, and that of medium strength aluminum alloy conductors has been 52.5%. IACS has been upgraded to 57% IACS to fill the energy-saving wire blank in China's 30mm ice area, which is a domestic initiative. Large section steel core medium strength aluminum alloy stranded wire JLHA4/G2A-1250/100 can be applied to areas with ice thickness up to 30mm and general areas. It can increase the conductivity of aluminum alloy under the premise of satisfying the strength and make the transmission loss of the circuit. Reduced by 8.6%, with considerable economic benefits.

Zhongtian uses a large-section one-step molding and aluminum wire structure to meet the environment's requirements for UHV eco-environmental protection. Feng Zhuhua, deputy director of the Institute of Conductive Metals, said that the use of line structure in line transmission can reduce the ice and wind loads on the line, effectively reducing line losses, radio interference and audible noise, and reducing the project investment costs and operating costs. It is an important technological measure to achieve energy conservation and consumption reduction in the power grid and promote environmental protection. The 1250mm2 steel-core aluminum stranded wire JL1X1/G3A-1250/70 and the aluminum alloy aluminum core wire JL1X1/LHA1-800/550 developed by Zhongtian Technology are the new cross-section energy-saving conductors in China, satisfying With regard to all the performance requirements of ACSR, the diameter of the wire is reduced by 8.7% over the outer diameter of the round wire structure, effectively reducing the ice-covering load and wind load, reducing the cost of tower construction and improving the ecological environment of the line.

Service UHV relies on technological support

Shanghai Zhongtian Aluminum Wire Co., Ltd., a subsidiary of Zhongtian Technology, has gone through a decade. In the past ten years, the company has adhered to the development direction of UHV power grid construction, adhered to scientific and technological innovation, and adhered to the major competitiveness of large-span, heavy-ice, large-section, energy-saving, and capacity-enlarging wires, and a number of products including the latest in the country. Product and latest technology. "The special wire to find Zhongtian" has become the consensus of the industry.

Zhao Lianjun, Dean of the China-day Institute of Science and Technology and professor-level senior engineer, said that Zhongtian Technology united with Shanghai Baosteel, Shanghai Cable Research Institute, Shanghai Jiaotong University and other organizations to organize a strong research team to strengthen independent innovation, from new materials, new technologies and new technologies. On the new structure, the technological content has been continuously improved to adapt to the application of special wire products in a wider range, which has enabled the efficient allocation of special wire resources, the serialization of production and manufacturing, and the standardization of key technologies to reach the international advanced level.

Zhongtian Lead Metals Research Institute is centering on the development of the wire manufacturing industry, adhering to the market-oriented approach, taking new product development as a leader, implementing a project manager responsibility system, and fully serving the market. Five areas of research have been carried out: market application research, basic materials research, production technology research, detection technology research and metal fitting technology research.

The Institute of Conductive Metals has successively developed 60% IACS conductivity heat-resistant aluminum alloy wires, high-strength heat-resistant aluminum alloy wires, medium-strength aluminum-magnesium-silicon alloy wires, high-strength aluminum-magnesium-silicon alloy wires, and energy-saving aluminum alloy core aluminum strands. Lines, energy-saving high conductivity aluminum stranded conductors, diameter-expanding conductors, double-capacity conductors, gap-type conductors, and wire-type structural conductors are widely used in over 90% of UHV projects in China. Ju Wei, Director of Zhongtian Science and Technology Institute of Leading Wires, was appointed as an UHV technical expert by the State Grid.

Feng Aijun, deputy general manager of Shanghai Zhongtian Aluminum Line, said that in the past ten years, Zhongtian Aluminum has strengthened its technical cooperation with the State Grid, China Southern Power Grid, China Electric Power Research Institute, State Grid Electric Power Research Institute, and North China Electric Power University. In UHV power grids, theoretical research and technological innovation of transmission lines were carried out, which made a positive contribution to UHV power grids in China. However, this is only the starting point. We will follow the pace of the sustainable development of the State Grid and China Southern Power Grid and create new ones. A decade of glory!