Under the role of liquid helium temperature and liquid nitrogen temperature, conductor loses resistance, current through no heat, no loss, and can be unchanged for several years, permanent flow, forming "superconductivity." In liquid helium temperature called low temperature superconducting technology, in liquid nitrogen temperature called high temperature superconducting technology.

liquid helium

Using superconducting magnets, magneto-fluid generators can be made. In addition, there is superconducting storage energy, superconducting high-speed suspension train, such as the successful development of the southwest Jiaotong University liquid nitrogen high temperature superconducting suspension train, the car in liquid nitrogen temperature, the maximum suspension weight of 700 kilograms, can carry 4 people. Superconducting cable.

A novel HTS power transformer, which uses liquid nitrogen instead of insulating oil, is about 15 times more powerful than the world's first HTS power transformer, which went on the market in March 1997. The transformer, made by Electricite de France in collaboration with ABB, has a power capacity of 10MVA and has been operating online since about 2000. In the future, it is ready to manufacture transformers of 30MVA for commercial use.

Liquid helium in superconducting technology

The key of this technology is to replace the insulating oil used in the copper coil of power transformer with the liquid nitrogen which is cheap and beneficial to the environment. In this way, the occurrence of fire can be eliminated, the risk of spillover can be eliminated, and insurance costs can be reduced. And the transformer can be installed close to large load centers, even in large cities in these places can be installed safely. This type of transformer has lower energy loss, which can reduce emission, improve equipment efficiency and reduce total cost of ownership.