From
above all the results, the conclusions are gained as
follows: a) the PD or the breakdown failures caused
by the metallic particles fixed or free movement in the
high volt apparatus insulated gases could be detective
with the UHF method; b) the method possesses an fair
advantage that conveniently realizes the operation
conditions monitoring of on-line; c) PD caused be the
different defects and different operating conditions
possesses different characteristics and could be
extracted and take as failure recognizing modes of the
high volt apparatus during operation and d) the
detective approaches could readily be made a portable
monitoring device easily utilized by the users.