Reliability Analysis on Crucial Subsystems of a Wind Turbine through FTA Approach

Abstract

The wind turbine reliability is a crucial factor for the successful operation of a wind power plant, affecting its availability and efficiency. Operation and maintenance costs affect the performance of the whole system and reinforce the necessity of redesign of specific sub-assemblies achieving lower energy production costs. At the first stage, field data make up Weibull sets in order to form the appropriate distribution-curve of the failure rate in each corresponding top event, are presented. These sets are limited to sub-systems having not only adequate data of the corresponding top events, producing more realistic results, but also having great risk priority, according to FMEA approach. These Weibull sets are linked with the corresponding top event of each subsystem and used to quantify the failure rates. The validation of previous studies made on wind turbine reliability FMEA analysis through the FTA method is investigated in this paper, as well as the results from previous studies made on reliability of wind turbines using the FMEA method. Though, the reliability and importance results as derived from a quantitative analysis, seem to be following the same trend like previous studies from different and various approaches. As a result, Electrical and Control systems as far as the Hydraulic System need to be re-designed with better performance and reliability since they are crucial for the operation of each WT separately as well as for the whole wind farm.