A renewal-process-based component outage model considering the effects of aging and maintenance

The development of accurate component outage models for reliability assessment in power systems is a fundamental problem. Traditional outage models with constant failure rate cannot reflect the impact of changes in operating conditions and repairs after a failure. In this paper, a staircase function is used to approximate the aging failure rate curve, and a renewal-process-based model is introduced to calculate time-varying failure probabilities. The proposed time-varying outage model is able to reflect the effects of component aging and repair activities on the failure rate. Application to an actual transformer shows that given the aging failure rate curve, the new model can evaluate the life probability distribution and steady-state availability of a component as accurate as the simulation method. Compared to the traditional constant-rate model, the proposed model is more accurate and practical.

► We propose a renewal-process-based component outage model.
► The failure rate in this model can be time-varying.
► The model is able to reflect the effects of component aging and repair activities.
► This model can be used in power system reliability assessment.