©ISTOCKPHOTO.COM/XIJIAN By Renchang Dai, Guangyi Liu, and Xing Zhang Transmission Technologies and Implementations Building a Stronger, Smarter Power Grid in China Digital Object Identifier 10.1109/MPE.2019.2957623 Date of current version: 19 February 2020 march/april 2020 T THE STATE GRID CORPORATION OF CHINA HAS been deploying ultrahigh-voltage (UHV) ac technology on a large scale since launching its Strong and Smart Grid plan in 2009. China has 80% of its hydropower generation in the southwest and 76% of its coal generation in the northwest. However, more than 75% of the country's energy demand is distributed in the eastern and southern coastal areas. This geographical mismatch between supply and demand made it necessary to build UHV transmission 1540-7977/20©2020IEEE ieee power & energy magazine 53http://www.ISTOCKPHOTO.COM/XIJIAN