Stochastic modelling of a cold standby unit working in a power plant system

  • Upasana Sharma *Department of Statistics, Punjabi University, Patiala
  • Gunjan Sharma *Department of Statistics, Punjabi University, Patiala
Keywords: Standby systems; semi Markov process; Regenerative point technique.


The present paper deals with the reliability analysis of a cold standby unit which is functioning in a power plant system. The main components of a power plant system are turbine and boiler. In this paper, we analyze the model which comprises the components of a system: one Turbine, one main high pressure boiler, two low pressure boilers which act as a cold standby unit for main high pressure boiler, one Primary Air (PA) fan, one Forced Draft (FD) fan and one Induced Draft (ID) fan. The provision of two low pressure cold standby boilers acting as a cold standby unit for main boiler has been introduced for smooth functioning of a system in case of failure in main high pressure boiler. Both the standby boilers operate together. If failure occurs in any of the main components of a system, the whole system comes at halt. When both main and standby unit stops functioning, the system goes to failed state. There is only single technician facility available for both purposes: repair as well as replacement. The computation of various measures of system effectiveness such as Mean time to failure of system (MTTF) and Profit has been done using semi Markov process and Regenerative point technique.


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