World's First UHV DC Power Line Repair Operation by Helicopter Completed

A helicopter was used to repair the section of the ±800 kV power transmission line between Inner Mongolia autonomous region and Shandong province in Linzhang county of Handan in Hebei province on June 18.

It was the first time in the world that repair on an operational ultra-high voltage (UHV) direct current (DC) power transmission line was operated by a helicopter. It was a breakthrough in China's technology of working on a live grid.

There are few countries now using helicopters in maintenance and amendment of main power grids. The method is quick and highly-efficient but is also on the cutting-edge.

Compared with traditional maintenance of an in-operation grid, the June 18 proceedings were much safer for employees, who no longer needed to climb onto the power line, to enter the electric field or to closely trace the line's shortcomings.

The maintenance was carried on by the State Grid Corporation of China (State Grid) and technical training and a simulation operation were conducted in advance.

The operation eliminated problems of the UHV line and guaranteed safe operation of the power grid, offering a reliable power supply for prevention and control of the COVID-19 pandemic and resumption of work.

A safe and stable grid will also meet the power consumption peak in summer.

With the rapid development of UHV construction, State Grid has been pushing forward its exploration of technical operations on working lines and strengthening the external load operations technology of helicopters.

So far, the company has mastered key technologies of using helicopters to carry on engineering on in-service grids, giving it an international lead in the field.

A helicopter is used to solve problems in the section of the ±800 kV power transmission line between Inner Mongolia and Shandong in Linzhang county of Handan in Hebei province on June 18. [Photo/sasac.gov.cn]

Baskets used to drop workers to repair the power line are hung from a helicopter. [Photo/sasac.gov.cn]

The helicopter is ready to take off for the repair mission on June 18. [Photo/sasac.gov.cn]

(Executive editor: Wang Ruoting)