To eliminate the arc-overvoltage in 6～35 kV power systems

an improved arc-overvoltage suppressor

named B-type arc-overvoltage suppressor

is proposed.When single-phase arc-grounding appears

the suppressor can control a high-voltage vacuum contactor to ground the fault phase bus to avoid the arc-overvoltage

or only operate to give an alarm signal without grounding operation

according to the preset operation mode for it.Two arc-overvoltage suppressors（B-type） may be configured for a 6～35 kV power system

where one is used as an arc-overvoltage suppression device and the other as an intelligent potential transformer cabinet.Each of them can be the backup device for the other.The practical application shows that the B-type arc-overvoltage suppressors can eliminate the arc-overvoltage in 6 ～35 kV power systems if their configuration

selection and application are correct.