Damped AC voltage method is widely used in partial discharge（PD） detection of power cable. The frequency of damped AC voltage changes with the length of testing cable. To investigated PD characteristics of defects in the heat-shrinkable cable accessories under damped AC voltage with different frequencies

four different artificial defects are set in cross-linked polyethylene（XLPE） cables. These defects include the cable terminal without stress tube

the middle joint with insulation tape instead of semi-conductive adhesive tape

the void and the metal particles on the surface of XLPE insulation. Furthermore

some characteristic PD parameters

such as the partial discharge inception voltage

the partial discharge extinction voltage

the discharge amplitude

and the discharge times

are compared and analyzed at different damped AC frequencies for PD pattern recognition of the four defects. The results show that the partial discharge characteristics are different as the damped AC frequency changes

and the statistical characteristics of four defects can be discriminated clearly

which indicates that this DC pattern recognition method is of good performance and is practically applicable.