Affection of Sensor Information Accuracy for Condition Based Strategy of GIS/GCB Maintenance

Condition Based Maintenance (CBM) is a new maintenance strategy and interest of utilities for reliable operation of aged power equipments. Although CBM has been tried to apply for various equipments, since an affection of accuracies of condition information from sensor have not sufficiently discussed, specification of reliable information is still not clear and CBM has not widely applied in actual power substation. The affection of accuracies of condition information for the criteria of failure recognition is treated in this paper. Authors retrace to the potential—failure curve (P-F curve) in original Reliability Centered Maintenance (RCM) concept and explain the affection. The explanation is proved using comparison with original sensor for CBM and existing sensor in SF6 gas slow leakage detection experiment. As a result of experiment SF6 gas leakage less than 0.1%/year might be detected using CBM sensor. The authors concluded that special performances in sensitivity and long term stability of sensor are very important for reliable operation of power substation under CBM strategy.