Two-layer observer-based FDI with application to NREL 5 MW wind turbine model

In this paper, a two-layer fault detection and isolation (FDI) scheme with application in wind turbines is presented. Commonly, model-based FDI concepts use a suitable mathematical model of the plant as a redundancy for on-line available data such as measurements and control outputs. In addition, the proposed two-layer concept exploits the redundancy between component and structure models at their common physical interfaces. It is shown by a illustrated example how the FDI problem can be formalized to a two-layer scheme. First, the models of both layers are proposed, a observer is derived for the component-layer and combined with the structure-layer. Applicability is shown by means of the NREL 5 MW reference wind turbine with objective of detection and isolation of parameter faults in the blade slewing bearings and blade structure.