Jiangsu launches joint operation to battle freezing weather

As a sudden freezing rain swept through Jiangsu in February, the eastern Chinese province has launched coordinated operations to safeguard local power safety, letting residents and enterprises be unaffected by the cold spell.

On Feb 19, the first cold wave in the Year of the Dragon came, with freezing rain and sleet — a spectacle not seen for many years — hitting Suqian in northern Jiangsu, bringing severe icy conditions to local roads and ice on some power grid equipment, as well as icing on transmission lines and line gallop.

The local branches of the State Grid — the world's largest utility shouldering a dual task of safeguarding the nation's energy security and economic lifeline — made brisk operations to avoid power outages.

The State Grid Jiangsu Power Supply Co arranged its subsidiaries in the prefecture-level cities of Suqian in the north, as well as Suzhou and Wuxi in the south to kick off a joint operation to rid of the situation, where line tripping, wire clip breakage and even tower toppling are possible without proper countermeasures.

Wu Zongzhan, a staffer from the State Grid Suqian Power Supply Co, said the provincial unit of the State Grid demanded them to carry out a trans-regional deployment of support forces, forming a team of over 120 people to examine 21 monitoring points of "three-span" transmission lines, which span expressways, high-speed railways and other important arteries.

The provincial unit also required a 24-hour monitoring of key transmission lines of 220 kilovolts and above, in a bid to prevent the lines from gallop amid the freezing rain and gale, and ensure their safe operation.

Wu noted that in addition to personnel inspections, they also sent drones to de-ice the power lines, as well as relied on night-vision monitoring equipment and other equipment to guarantee and improve the reliability of grid power supply.

Wang Donglin, from the State Grid Suzhou Power Supply Co, told his counterparts in Suqian: "The Su'an 5K73 electric transmission line from the 500KV Suyu substation to 500KV Anlan substation is free from gallop and everything is normal. You can rest assured."

Wu's colleague Li Mengyao said that in addition to the impact of rain and snow on power transmission lines, the normal operation of substation equipment has also been affected.

"During the cold wave, we focused on increasing equipment special patrols on and infrared temperature measurement, paying close attention to oil filling and inflation equipment," she said, adding they also relied on automatic inspection robots and multi-functional monitoring cameras to ensure the stable operation of substations.

To minimize the effect of the severe weather on grid equipment, the Power Dispatching Control Center of State Grid Suqian Power Supply Co also attached much attention to weather changes and the variation trend of power load, so as to scientifically adjust the power grid operation mode in line with the load changes, said Guo Panpan, also Wu's colleague.

Liuzizheng@chinadaily.com.cn