Key Technologies for Field Installation of Converter Transformers in the Yunnan-Guangzhou ±800 kV UHVDC Transmission Project

Based on the experiences in field installation of the Huidong Converter Station of Yunnan-Guangdong ± 800 kV UHVDC transmission project,the key techniques for installation of the converter transformers are introduced.Installation of the 800 kV converter transformer is much more difficult than that of conventional transformers.The main difficulties include cleanness control of the installation environment,installation of valve bushing turrets and valve bushings,coolers installation,converter transformer oil treatment and traction in place and so on.