Recently, the cable system consisting of 750kV ultra-high voltage cross-linked polyethylene insulated power cable and three major connectors independently developed by China has successfully passed the authoritative electrical type test of the Electric Power Industry Electrical Equipment Quality Inspection and Testing Center of the China Electric Power Research Institute, marking a major breakthrough in the research and development and manufacturing of my country’s ultra-high voltage transmission core technology and complete equipment.
Transmission lines are the lifeline of social development. Transmission methods are mainly divided into overhead transmission lines and cable transmission lines. China’s UHV 1000kV overhead transmission technology is the world leader.
As early as 2009, my country has put it into use globally. However, cable transmission still faces more technical challenges such as cable connectors and insulation materials. Since a Japanese company developed the world’s first 500kV cross-linked polyethylene cable in 1988, the voltage level of the cable has not been broken through by the industry for 36 years.
Yang Liming, former chief cable expert at the State Grid Electric Power Research Institute and current chairman of the Wire and Cable Professional Committee of the China Standardization Association, said that this breakthrough is the first time that the global cable industry has passed the complete 750kV cable line type test by a national authoritative agency, including the line composition of 750kV cross-linked polyethylene insulated power cables, gas-insulated composite sleeve outdoor terminals, combined prefabricated intermediate joints, and dry GIS terminals. This marks another major breakthrough in my country’s core power technology equipment after UHV transmission technology, and is at the world’s leading level in this field.
It is understood that the 750kV cross-linked polyethylene insulated power cable used in this test was independently developed by Jiangsu Shangshang Cable Group (referred to as “Shangshang Cable”), and the three major accessory products were independently designed and developed by Jiangsu Anke Intelligent Electric Co., Ltd. (referred to as “Anke Intelligent Electric”).
According to relevant persons in charge of Anko Intelligent Electric, the key technology of UHV cable lines is cable connectors. Anko Intelligent Electric has successively overcome the problems of high-temperature vulcanization dynamic management of large-model polymer materials, DSC scanning and step-by-step curing, thermal effects of large-model UHV cables and accessories, isothermal surface distribution and effective heat dissipation. It took a year and a half to achieve major breakthroughs in a series of key processes and production and manufacturing technologies, and finally completed the research and development of 750kV cable connectors.
The successful passing of the type test of the 750kV cable line not only demonstrated my country’s strength in the design, research and development, and manufacturing of UHV cable systems, but also laid a solid foundation for the subsequent design consolidation, standard setting, mass production and network operation of 750kV cable systems, which is of positive significance for China’s cable industry to lead the world.