China's first high-temperature superconducting low-voltage DC cable grid operation, to fill the domestic gap

On November 20, 2023, Yongding undertook the construction of my country's first high-temperature superconducting low-voltage DC cable, which was connected to the grid and put into operation in Suzhou, Jiangsu, filling the gap in the application of superconducting cable low-voltage DC systems in my country.

In June 2020, Jiangsu Etern Co., Ltd. Suzhou Wujiang District Government and State Grid Suzhou Power Supply Company jointly launched the construction of a high-temperature superconducting DC cable demonstration project. On the basis of the medium and low-voltage DC distribution network in Tongli, Wujiang, a 180-meter-long high-temperature superconducting DC cable will be built to connect the 10kV Pangdong DC Center Station and the DC distribution room in the factory area of Hongsheng Plastic Technology (Suzhou) Co., Ltd.

The high-temperature superconducting low-voltage DC cable in this project is designed and manufactured by Eastern Superconducting Technology (Suzhou) Co., Ltd., a wholly-owned subsidiary of Yongding Co., Ltd., and the second-generation high-temperature superconducting tape used in the cable is also produced and provided by Eastern Superconducting, realizing the localization of the core materials of the superconducting cable system. Professor Gu Hongwei, member of the Superconducting Technology Professional Committee of the Chinese Electrotechnical Society and director of the Eastern Superconducting Academic Committee, introduced: "Compared with AC superconducting cables, DC superconducting cables will further reduce the line loss of the power grid." In terms of structure, the cable uses the positive and negative coaxial method for the first time in China, which is equivalent to two cables combined into one. It is currently the most compact superconducting cable. The advantage is that the opposite flow direction makes the magnetic fields generated by the positive and negative poles cancel each other out, realizing complete magnetic field self-shielding, thus eliminating external electromagnetic interference, and in the fault state, it can also have the function of current limiter, protect other electrical equipment in the system, and make the power system more reliable.

The application of DC superconducting transmission technology injects strong impetus into the construction of new power systems and energy transformation and upgrading. In the future, Yongding will continue to play the leading role of the industrial chain, actively promote the deep integration of superconducting upstream, midstream and downstream innovation chains with the industrial chain, promote the synchronous research and development, production, verification and application of superconducting materials and advanced equipment, and strive to build a modern superconducting industrial system with independent control, complete system and advanced safety.