Overview of the recent developments of ultra high voltage AC transmission in China

The delvelopments of ultra high voltage (UHV) alternating current (AC) transmission in China were reviewed in this paper. The UHV AC transmission historical developments in the past twenty years; the research results of the UHV key technologies including electromagnetic environment, overvoltage and insulation coordination, lightning performance, live-line working, equipments manufacture in the recent years; the design parameters and construction of UHV AC experimental and demonstration line, and UHV AC test base were introduced.