抄録
Statistical calculating programs simulating partial discharge appearance are developed and applied to evaluations of criteria for descrimination of the partial discharges from noises. According to the simulation, clusters of sequential pulses appear at the partial discharge inception voltage, which have never been utilized at an usual pattern recognition of the partial discharges. Two original indexes those are a pair pulse rate and a maximum sequential pulse rate are defined to describe the time sequential features of the partial discharge and their signal distinguishable capabilities from noises are evaluated. A new logical index describing the signal distinguishable capability of an usual φ-q pattern of the partial discharges from the noises is also proposed and compared with those of cluster pulses. The maximum sequential pulse rate gives most sensitive criteria in the bounds of calculating conditions.
A 66kV cross-linked polyethylene cable with an artificial defect is used to detect cluster pulses. By adding noise pulses twice as much as measured partial discharge pulses the usual φ-q pattern criteria becomes powerless but cluster pulse criteria still infomative on the recognition of the partial discharges.
