On the 22nd, the world’s first 35 kV kilometer-level superconducting cable demonstration project was put into operation in Shanghai, marking a major breakthrough in this key technology in the field of new domestic power system construction, effectively solving the problem of narrow-channel large-capacity power transmission, and helping Eliminate power supply "stuck necks" in load hotspots.
It is reported that the 35kV kilometer-level superconducting cable demonstration project is located between the two 220kV substations, Changchun Substation and Caoxi Substation in Xuhui District, Shanghai. The line is 1.2 kilometers long and has a design current of 2200 amperes. It is the first domestic construction of the State Grid. The superconducting power transmission project is the 35 kV high temperature superconducting cable with the largest transmission capacity, the longest line, and fully commercial operation in the world.
The principle of superconducting power transmission is to use the superconducting properties of superconducting materials in a liquid nitrogen environment of minus 196 degrees Celsius to make the power transmission medium close to zero resistance and power transmission loss to zero, thereby realizing large capacity at low voltage levels Power transmission.
The demonstration project was constructed and maintained by the State Grid Haidian. The project took more than 5 years from its inception in 2016 to the full line of operation; the main part of the project started in April 2020 and took 1 and a half years to complete.
"A 35 kV superconducting cable is equivalent to the transmission capacity of a traditional 220 kV cable, which can replace 4 to 6 traditional cables of the same voltage level, saving 70% of the underground pipe gallery space than before." Xie Wei said that such significant advantages in transmission efficiency and space economy make superconducting cables suitable for direct transmission of large-capacity electrical energy to urban centers where a lot of money is available.
At present, the research and development of superconducting power transmission technology is in the ascendant all over the world. In the past 15 years, Shanghai has continued to support the R&D and industrialization of high-temperature superconductors, and has formed core capabilities from superconducting materials to cable integration.
In the next step, Shanghai will make every effort to promote the creation of a superconducting industrial highland with global influence. The first is to in-depth study the reliability and economy of superconducting cables, and to promote the transformation of superconducting cables from "samples" to "products"; the second is to break through key core technologies such as low-cost preparation of high-temperature superconducting materials, and create innovative superconducting technologies. The place of origin; the third is to continuously expand the application of superconducting in the fields of maglev and controllable nuclear fusion; the fourth is to build an international exchange platform to create a gathering place for the development of the superconducting industry.