Sensors for Condition Based Maintenance in GIS/GCB

In Japan, about 30 years have passed since gas insulation equipment began to be operated. This old equipment must be maintained. But, when viewed in lower costs, life time extension is expected with minimum maintenance. For its purpose, maintenance style must be changed from TBM which implements maintenance every constant period to CBM which changes maintenance schedule by the condition of the equipment. TBM is the conventional style and CBM is the future style. Moreover, CBM has various styles such as RCM and RBM. RCM means reliability centered maintenance, and RBM means risk based maintenance. However, even if the maintenance changes to any style, the maintenance style called SBM (sensor based maintenance) is necessary to acquire the information. We developed and evaluated the sensors for SBM-gas pressure sensor for detecting slow-leakage, SF6 decomposition gas sensor for detecting overheat conductor (poor contact), and partial discharge sensor for insulation failure. We got the result that these sensors were suitable for CBM.