500 kV overhead transmission lines usually use double ground wires

for one is GJ ground wire

the other is OPGW（operticalfible composite overhead ground wire）ground wire. Previous study has proved that segmented insulation with middle point grounding of GJ ground wire and segmented insulation with one-point grounding of OPGW can not only limit induced voltage

induced current

and power loss

but also have reliable performance of protecting from lightening. The model of one actual 500 kV transmission line of Jinghua in Zhejiang province is set up by EMTP

connecting to State standard（GB 50545—2010）and the standard of the power industry（DL/T 832—2003）to study and compare the induced voltage

induced current and power loss of ground wires with different grounding methods. What is more

it will be the evidence to improve the grounding methods of ground wire.