State-space characterization and estimation of unavailability costs of a wind turbine

Abstract

Nowadays, the wind turbines are the principal source of wind energy production. However, the information known to the public of these machines is still very low. Information related to failure modes and maintenance of these systems is confiidential and only the manufacturer knows. Nevertheless, knowledge about on its functioning, namely its principle states and failure modes are essential to analyse reliability and to define the better maintenance policy to be applied. Based on this gap, 21 identical turbines, from a wind farm located in Portugal, were observed during two years. This paper describes and analyses the main states observed in a wind turbine. Specifically, it examined the frequency of the occurrence of these states in two years and also the time spent in each of these states. The study emphasizes the Pitch Control Device by being a system of special importance, particularly in terms of efficiency of the turbine and safety of persons and property.