Sichuan-Tibet Interconnection Delivers 1.5 TWh of power to Tibet in past 5 years
Over the past five years since its operation, Sichuan-Tibet Grid Interconnection Project has delivered about 1.5 TWh of electricity to Tibet, injecting strong impetus into local socioeconomic development.
The Project embodies the concrete efforts of State Grid to implement the central government's requirement during the Tibet Work Forum, carry out Western China Development Strategy and support Tibet’s development. Operated on November 20, 2014, it eliminated problems of severe power shortages in Qamdo, a prefecture-level city in Tibet, and in the southern regions of Garze, an autonomous prefecture in Sichuan. It also ended Qamdo grid's isolated operation and realized interconnection with Sichuan Province, securing energy supply for the development in eastern Tibet, southern Garze and the upper reaches of the Jinsha River and the improvement of people’s livelihood in Tibetan areas.
With the total length of 1,521km, the Project starts from Xiangcheng County, Sichuan in the east and ends at Qamdo, Tibet in the west. It passes through the plateau in Sichuan and Tibet with extreme low temperature and oxygen level as well as frequent geological disasters, which brings significant challenges to logistics and construction.
The Sichuan section of the Project, with 1,557 towers, spans 1,151.4 km across 7 counties of Qamdo, Garze and Liangshan. Its operation and maintenance are difficult in depopulated areas due to zero communication signals, strong sunshine, low temperature, frequent disasters such as earthquakes, mountain collapses, landslides and debris flow, and high-frequency lightning strikes occurring 70 days a year on average. In order to operate, maintain and repair the transmission lines in this section, Sichuan Electric Power Transmission and Transformation Co., Ltd., a subsidiary of State Grid, takes a raft of measures: It works with the government to establish early-warning mechanisms to tackle geological and weather incidents; monitors and rectifies defects and potential hazards in a timely manner through regular monitoring and special inspections according to regions and managerial levels; uses advanced equipment and facilities such as distributed traveling-wave-based detection devices, icing on-line monitoring facilities and mountain fires on-line monitoring equipment, and even involves drones to accommodate high-altitude plateau, which can substitute human inspections in extreme environment, effectively improving the lean maintenance and ensuring stable operations.
As a critical hub of the Project, the 500 kV Batang substation is designed to deliver electricity to Qamdo and transmit power outwards from hydropower station along the Jinsha and Lancang rivers. To ensure its safe and stable operation, the O&M team from State Grid Sichuan Maintenance Company constantly exercises lean operation, and explores new ways to manage high-altitude power grids, taking full responsibility for the equipment under their care. They have built a “four-in-one” comprehensive analysis platform, and continuously carry out “daily comparisons, weekly analyses and monthly summaries” to ensure the safety of the power grid.
“After the Southwest power grid began asynchronous interconnection operations on June 19 this year, it has become more difficult to operate and maintain 500kV power grids in remote regions,” said Yang Yijie, the head of the Batang substation. "We ensure the stable operation of the Batang substation by strictly implementing all on-site rules and regulations, actively integrating operations and inspections, and promoting lean management and accident drills, among other measures.”
To date, the Sichuan-Tibet Grid Interconnection Project has operated safely for 5 years. O&M personnel have eliminated a total of 3,037 potential hazards, 178 of which are classified as “critical” and 720 as “severe”.