Availability of generating units operated discontinuously

Some of the important aspects for reliability assessment of power systems are outlined to quantify a desired security level. This quantification eliminates subjective guesswork, and enables efficient prediction of future operating conditions.This requires simple and computationally efficient models. A realistically efficient availability model of a generator unit operated in a 5-state discontinuous cycle is presented. Typical work schedules and transition rates have been analysed. This showed that the work schedule significantly affected the meanoutage probability, and the random-transition rates greatly affected the periodic fluctuations between minimum and maximum-outage probabilities.