Affected by the cold wave, in February 2024, frequent low-temperature rain, snow and freezing weather occurred in Qiandongnan Miao and Dong Autonomous Prefecture in eastern Guizhou. The 110kV Huaigu line of Kaili Power Supply Bureau of Southern Power Grid in Guizhou was repeatedly covered with ice, threatening the safety of line power supply. The new IGCT-CSC DC ice melting device installed in Kaihuai substation accurately identified the line ice cover, and quickly started the line automatic reversal ice melting operation, completing the line ice melting work for many times, ensuring the safe and stable operation of the power grid.
The new IGCT-CSC DC ice melting device is the world's first IGCT-CSC DC ice melting device jointly developed by DC Research Centre of Energy Internet Innovation Research Institute of Tsinghua University, Guizhou Grid Electricity Academy of Sciences and Beijing Sifang Relay Automation Co. Compared with the thyristor half-controlled current source and IGBT fully controlled voltage source scheme, the project innovatively puts forward the PWM fully controlled current source (PWM-CSC) converter ice melting technology route based on the direct series connection of IGCT devices, breaks through the multi-device series connection of voltage equalisation and active damping control technology, and adopts 8 domesticated IGCT-Plus devices in direct series connection for each bridge arm, which is small in size, low in cost and has outstanding advantages of high efficiency, It has the outstanding advantages of small size, low cost and high efficiency.
The operation process will not cause harmonic pollution to the power grid, and the output DC voltage is continuously adjustable from 0 to 10kV and the output DC current is continuously adjustable from 0 to 1kA. In addition to the line ice melting function, it can also realise reactive power compensation and power quality management functions. In addition, the project also puts forward the operation scheme of DC ice melting device with intelligent start-stop and automatic phase change, which can automatically identify the ice cover of the line, automatically start the ice melting operation, and automatically change the phase to operate the melted transmission line, thus improving the efficiency of ice melting.
With the gradual maturity of IGCT device technology, IGCT-CSC converter technology can also be expanded to large-capacity DC power supply scenarios such as electrolysis hydrogen production, metallurgy, etc., which can significantly improve the traditional thyristor power supply occupying a large area, harmonic and reactive power consumption and other problems.
IGCT-CSC DC ice melting device of Kaili Power Supply Bureau of Guizhou Power Grid
IGCT-CSC DC Ice Melting Device Topology
