Guangzhou - On November 24, the Kunbei-Longmen pole 2 high- and low-end converter of Kunliulong DC Project operated for the first time, to steadily increase the voltage from 680 kV to 800 kV.
This marked the Kunliulong DC Project entering an era of being able to transmit power of 800 kV and a worldwide first to transmit power over long distance by applying LCC/VSC-UHVDC and VSC-UHVDC …itself a milestone in the development of DC transmission.
With the same remarkable transmission capacity, the higher the voltage, the lower the current and so is the resulted loss. In the history of global power industry, increasing voltage, via power transmission system, has been a realistic goal for scientists.
Though VSC-DC performs much better than DC in terms of flexibility, its voltage was once considered much lower. In this virgin territory, the technical team of Kunliulong DC Project made breakthroughs in series control of the VSC-DC high and low valve sets, charging with short circuit in the DC side of the full-half topological converter and online run and stop technology in VSC-DC high and low valve sets.
The China Southern Power Grid engineer team cleared the technical obstacles for increasing the voltage of VSC-DC to 800 kV and achieving LCC/VSC-DC transmission through simulations, calculations, and experiments, especially system tests.