Stochastic modelling of failure interaction: Markov model versus discrete event simulation

Markov models have traditionally been used to model failure interaction of load sharing parallel system to evaluate the availability of systems. However, complexity of the Markov model increases as the number of components in parallel increases, also solving the Markov model requires high level mathematics and hence practicing engineers find it difficult to model, solve or interpret the results using this. Discrete event simulation (DES) is a more versatile modelling technique that can also be used to model failure interaction. A next event based simulation algorithm is designed and coded in MATLAB 7.0. The Markov and DES model is applied to a live case in Goa Electricity Department and the respective outputs are compared. A full factorial design of experiments is conducted on both the techniques and also statistical model adequacy techniques are conducted to ascertain the veracity of the model. The results indicate that DES model is as accurate as Markov model.