Reliability/availability of K-out-of-N system with M cold standby units

A generalized repairable system reliability model, K-out-of-N plus M cold standby units, is proposed in this paper. Reliability and availability of this system have been deeply studied under several combinations of assumptions/cases: identical and different cold standby, perfect and imperfect switching, and single backup and backup itself is a k-out-of-n system. Reliability evaluation of such systems is developed and provided. How to design this kind of power system to achieve its reliability requirements is studied and discussed. Factors that affect system reliability characteristics are presented. A real example of the defined system (on-site power plant) is provided through the developed approach. Reliability and availability of the power plant are evaluated, which is much-more reliable than the existing power sources. Further research and considerations are also discussed