Evaluation of Reliability and Availability Characteristics of 2-out of -3 Standby System under a Perfect Repair Condition

Many authors have studied the effectiveness of a redundant system under two or three types of failure under the assumption that such failures are repairable. Little attention is paid on whether such repair action can restore the system operating condition to as good as new (perfect repair) and the effect of such perfect repair on the system performance. In this study, various measures of system effectiveness such as mean time to system failure (MTSF), steady state availability, busy period and profit function of a 2-out-of-3 repairable system with perfect repair are analyzed using Kolmogorov’s forward equation method. Some particular cases have been discussed graphically. The results have indicated that perfect repair action plays a vital role on system performance. Simulations results show that perfect repair is important particularly in increasing mean time to system failure, availability and system performance as a whole.