A section of the 750 kV ultra-high voltage power transmission project in the Xinjiang Uygur autonomous region successfully crossed the Dushanzi Grand Canyon in Karamay on April 10.
The line set a new record for the longest span — 1,346 meters — in the history of UHV power grid construction in the region, according to State Grid Xinjiang Electric Power Co, the builder.
The section runs approximately 427.5 kilometers, connecting 750 kV substations established in Ili Kazak autonomous prefecture, Bortala Mongolian autonomous prefecture, Wusu city in Ili and Manasi county in Changji Hui autonomous prefecture.
An investment of 2.07 billion yuan ($301 million) was made for the section, on which construction began in June 2021. The goal was to be done and operating by Sept 20 this year.
It will boost power transmission capacity from Ili to Changji, ensuring a steady supply of electricity and meeting growing power demand in the region. It will also enable the optimal allocation of energy resources across different regions, contributing to the overall stability of Xinjiang's power grid. In doing so, it will provide dependable support for the region's economic development and social stability, the power company added.
The entire UHV power transmission project involves many crossing operations at 196 different sites, including railways, highways, power lines, forests and rivers. One of the most challenging places was Dushanzi Grand Canyon.
Crossing operations for the UHV power transmission project present a range of challenges, including distance, low visibility, and large fluctuations in sag caused by wind. This makes the installation of wires a demanding and time-consuming process that requires high precision.
To ensure the smooth operation of the crossing process, the builder conducted daily inspections of tools and key construction sites, identifying and addressing any potential safety hazards before proceeding, according to Wang Jia of the power company.
During the operation, the builder continuously monitored the wire installation, correcting any deviations to ensure the wires remained in the correct positions throughout the construction process, Wang said.