Deeply suppressing the switching overvoltage of UHV systems will reduce the manufacturing cost and technical bottlenecks of UHV power apparatus.Based on the 1 000 kV UHV project from Huainan to Wannan

the switching overvoltages were numerically analyzed.The effects of suppressing the overvoltage for measurements were estimated

such as setting arresters on both ends

cooperation between arresters and closing resistance

setting a set of arresters in the middle of the line

and setting several sets of arresters along the line.The effects of above methods in suppressing the switching overvoltages were compared

and the feasibility was analyzed in aspects such as aging characteristics

the withstand capacity of power frequency overvoltage

and energy absorption capacity.On the baisis of advanced surge arrester technology

we can decrease the ov

ervoltage level from 1.6 U

0

1

.7 U

0

to 1.2 U

0

1

.3 U

0

（U

0

=898 kV）

to realize the target to deeply suppress the switching overvoltage.