Skip to Main Content
Condition-Based Maintenance (CBM) of the electric transmission and transformation equipments has been carried out gradually in the State Grid Corporation of China (SGCC). Equipments' risk assessment is a challenging work during implementing CBM, because the failure probabilities of equipments may vary with changes in the operating conditions, and hard to predict accurately. In this paper, the Time-Varying Outage Model (TVOM) of equipments is applied in the risk assessment to solve the above difficults. To demonstrate the necessity and efficiency of the TVOM, a numeral test on transformer was given to compare the result of the statutory method in SGCC standard and that of the time-varying outage model.