Recently, State Grid Corporation of China posted news in the STATE GRID NEWS that the 500kV EHV cable which was the first time that SGCC purchased homemade cable used in Beijing Haidian and fabricated by Hanhe Cable has passed successfully the 6-days Commissioning Withstand Test on 8th June. 
      This test is AC variable frequency resonant commissioning withstand test with largest voltage and longest time in the world urban power grid. It is also the first experiment done withstand test and partial discharge test at the same time. This will make sure the installation quality and operational reliability. The success of the experiment significant that the 500kV 2500mm2 EHV cable independently developed by China could fully meet requires for large section and over long distances national EHV transmission lines, and the technical standards represent the world's leading. It also means that EHV cable developed by native national enterprises has entered the ranks of the world's highest voltage and rounded the Chinese cable industry's dream. 
      500kV cable system is that with the highest voltage in operation in the world now. The design and manufacturing represent the highest technical level in the cable industry. The homemade 500kV cable incoming line system in Beijing Haidian Substation provided a good opportunity for Chinese cable industry. This is of great significance to improve the development of HV, EHV cables and enhance the level of Chinese wire and cable manufacturing.

      The development and application of the world’s EHV cable started from the latest years of last century in Japan and Europe. But today, it will be developed in China in 21th century. China has already had the capability to develop the 500kV cable. Cable manufacturing companies have been accumulating experience of application and producing. They carry out in-depth researches and technology innovation. This makes the manufacturing technology and application technology of Chinese 500kV cable develop faster and walk in the forefront of the world. With the development and maturity of the homemade cables, the price fell nearly 27% than that of imported products. Therefore, supporting the development and progress of domestic cables has great economic and social benefits for reducing HV and EHV cable project cost and promoting the development of electric power industry.