On the 13th, the reporter learned from China Energy Construction Group that the 10 kV three-phase coaxial superconducting cable system, led by Shenzhen Power Supply Bureau and participated by Guangdong Electric Power Design and Research Institute (hereinafter referred to as Guangdong Institute) of China Energy Construction Group as a key core technology output unit, has provided assistance in effectively solving the problem of power supply in mega cities. In recent years, with the continuous growth of urban power load demand, a series of problems such as saturated transmission line corridors and difficult land use for power grid construction have become increasingly prominent, posing challenges to the power supply in the central areas of super large cities worldwide. According to the relevant technical leader of Guangdong Institute, in order to overcome this world-class problem, under the leadership and organization of the Shenzhen Power Supply Bureau of China Southern Power Grid, Guangdong Institute established a special technical research group in 2017. Afterwards, it conducted in-depth research on key technologies of superconducting transmission, participated in more than 10 experiments such as superconducting system tuning, cold and hot cycling, and heavy load testing, and edited the first international design standard for superconducting cable lines, And general contracting for the construction of a 10 kV Binhe to Xinghe superconducting cable demonstration project. Based on this demonstration project, Guangdong Institute, as a key core technology output unit, participates in the research and development of a 10 kV three-phase coaxial superconducting cable system and assists in the transformation and implementation of this technology achievement. The superconducting system adopts a new generation of high-temperature superconducting transmission technology, mainly composed of key components such as superconducting cable body, terminal, refrigeration system, protection device, etc. It can achieve low voltage level high-capacity transmission, providing a new solution for solving the power supply problem in super large cities globally, with significant economic and environmental benefits. According to reports, the diameter of the superconducting cable body is only 17.5 centimeters, with a total length of 400 meters, and a transmission capacity of up to 43 MVA, which is equivalent to the power transmitted by five conventional cables of the same level. It can simultaneously drive four high-speed trains at a speed of 350 kilometers per hour. Superconducting cable terminals are designed with structures such as vacuum multi-layer insulation and high-voltage isolation insulation, which can effectively reduce terminal heat leakage, improve insulation performance, and achieve a reliable transition from superconducting cables to conventional distribution systems. The superconducting cable refrigeration system uses liquid nitrogen as the coolant, overcoming technical difficulties such as efficient heat transfer, gas-solid coupling heat transfer, wear-resistant driving mechanism, and online hot swapping in the small space of the core equipment refrigerator. It is easy to maintain and provides a stable operating environment of -200 degrees Celsius for the superconducting system. In addition, the quench (loss of superconducting characteristics) protection device can accelerate tripping and perform self recovery control after a quench fault occurs in the superconducting cable, thereby achieving comprehensive protection of the superconducting cable. (New News Agency)