What are the key parameters of medium voltage switchgear in box-type substations?
On the 16th,the large-scale crossing of the Yellow River for the 800 kV high-voltage transmission project from Haminan to Zhengzhou was completed,and the ultra-high voltage transmission line successfully crossed the Yellow River.
The 2,210-kilometer high-voltage transmission line between Harbin and Zhengzhou is currently an ultra-high voltage DC project with high voltage level,large transmission capacity and long transmission distance in the world and will be completed in July this year.Crossing the Yellow River is a difficult part in the whole project construction,with a crossing distance of 3.9 kilometers,which requires high construction requirements for the foundation tower and also solves the problem of high tension in the erection of conductors.For this reason,in the foundation construction of the iron tower,for the first time,the type of inclined high column with low bearing platform is adopted.The diameter of the foundation column is 2 meters,and the height of the column is 9 meters.Each foundation uses more than 300 tons of steel bar.A total of five iron towers are built,of which two main towers are 147.1 meters high,which is equivalent to 50 stories high,thus becoming the high power iron tower in Henan.Henan Power Transmission and Transformation Engineering Company independently developed a 2×100 kN tension machine,which overcame the technical difficulty of large wire tension and ensured smooth stringing construction.
According to reports,after the Harbin-Zhengzhou UHV DC project is put into operation,it can provide more than 48 billion kilowatt-hours of electricity to Henan every year,equivalent to 22.1 million tons of coal being transported to Henan.