Long term reliability analysis of components of photovoltaic system based on Markov process

In this study, long term component reliability analysis of PV system is performed using Markov method. Four major components for evaluation of the system are considered with 16 different states to evaluate a PV system as a package with one reliability index. The probability analysis for each state shows that although at very first years the states of combination of multiple failures are negligible, after several years of operation, all states are effective in the reliability of the system. Based on Markov modeling given in the study and actual failure and repair rates of components, the reliability analysis shows that the reliability of the system decreases from 0.99 to 0.81 in 20 years. The initial condition for each year is gained from the final condition of the previous year. The annual value of the reliability of PV system makes the designers plan major maintenance and switching based on cost and load.