7Villas J E T, Portela C M. Calculation of electric field and potential distributions into soil and air media for a ground electrode of a HVDC system[J]. IEEE Transactions on PowerDeliverv, 2003, 18(3: 867-873.
8Zou J, Liu Y Q, Yuan J S, et al. Analysis of the toroidal HVDC grounding systems in horizontal multilayer soils [J]. IEEE Transactions on Magnetics, 2006, 42(4): 1435-1438.
9Ruan W, Ma J, Liu J, et al. Performance of HVDC ground electrode in various soil structures[C]//Proceedings of the International Conference on Power System Technology. USA: IEEE, 2002: 962-968.
10Greiss H, Mukhekar D, Lagace P J. Transient analysis of heat dissipation due to a HVDC ground electrode[J]. IEEE Transactions on PWRD, 1989, 4(2): 916-920.
