机车电传动 (Nov 2021)
Impact of Ground Current of HVDC Earth Electrode on High-speed EMU
Abstract
During the operation of HVDC system with the earth as the loop, the formed current field in the ground has corrosion effect on the adjacent high-speed railway system. A complete high-speed railway comprehensive grounding equivalent model and high-speed EMU electrical model were established, the existing DC path was analyzed, and the "Π" type equivalent circuit suitable for high-speed railway simulation modeling was extracted. The simulation models of various typical scenes of high-speed railway were established by using CDEGS software. Through the simulation analysis of different soil resistivity and vertical distance between grounding electrode and railway, the DC current flowing through traction power supply system and EMU under different external conditions was compared. The results show that there are differences in DC parameters in different high-speed railway sections. The higher the soil resistivity, the smaller the vertical distance between the grounding electrode and the railway, and the greater the DC current flowing through the traction transformer of EMU; When the soil resistivity along the line is less than 300 Ω·m and the vertical distance between the grounding electrode and the railway is more than 5 km, the DC magnetic bias effect of EMU traction transformer meets the requirements of the regulations.
