When taking earth as part of HVDC system loop, Grounding electrode system is connected to ground effectively, operation mode of which is different from normal HVDC lines. A ±500kV HVDC system model is established in this paper by using PSCAD/EMTDC simulation platform, based on which the fault operation characteristic of grounding electrode line is simulated and analyzed , and a fault location method based on the Bergeron line model aimed at single line grounded short circuit is also put forward in this paper. Head-end voltage and two outlets current after fault are used to calculate voltage distribution along line. According to the characteristics that the fault or electrode point is the minimum voltage along line, the fault location function is established to calculate the fault distance. The simulation result and project instances indicated that the fault of grounding electrode line can be located accurately with the proposed method.

HVDC；,grounding electrode line,Bergeron line model,fault location,voltage distribution