Power Efficiency and Availability Computation with Stochastic Events Models

The paper computes the outages time and economical damages for one year and presents the associated stochastic state-space model for an isolated fault-tolerant electric power system, modeling its failure-maintenance events. The most used models for the fault tolerant systems availability study are the state-space models, as generalized stochastic Petri nets (GSPN). A complex model appears when the simple systems are studied together with failure-maintenance actions, because of the logical subnet inside the model. If the state space properties and the high-level Petri nets proprieties are taken in account, the model is simplified and is easy to use for complex real systems, like the isolated power electric naval plant. For complex systems availability and efficiency analysis, a specific software application is needed. The stochastic Petri nets are adapted to create the system model and to compute the results like general or special availability indicators. The proposed methodology helps the specialists to handle easy and fast the efficiency and availability study and conclude the measurable results very needed in power system practice. The paper proposes an availability study for a real power study case system, to show its efficiency and the friendly use of the methodology.