There exist many reasons for the partial discharge in switchgear such as the insulation defect

insulationaging

and the lack of insulation gap and so on

so the judgment of partial discharge type is important for theevaluation of switchgear operation status. The internal structure of switchgear is analyzed

the features of differentdetection method are discussed and the decision and location method of partial discharge are given. Base on the 3 cases partial discharge

as for the employed detection method

the amplitude

characteristics

location

types andreason of partial discharge are researched

meanwhile

the sensitivity of the detection method under different cases isalso given. The testing data show that: TEV is more sensitive than AE as for the internal PD of arrester

UHF is moresensitive than TEV and AE as for the internal insulation PD of PT

AE and UHF is more sensitive than TEV as forthe surface PD of wall bushing. The research on the partial discharge characteristics of different electrical equipmentin the switchgear provides important parameters and basis for the condition maintenance of the high voltageswitchgear

and provides powerful technical support for the on-site test personnel.