Flatness-based disturbance observer for condition monitoring of marine power generation units

The article proposes a flatness-based disturbance observer for condition monitoring of the integrated power generation system, which comprises a marine turbine and a synchronous generator. It is proven that this power generation system is differentially flat, thus it can be transformed into an input-output linearized form and into the canonical Brunovsky form. For the linearized state-space description of the system, state estimation can be performed with the use of Kalman Filtering (derivative-free nonlinear Kalman filter). Moreover, by re-designing the Kalman filter as a disturbance observer, it becomes possible to estimate disturbances, model uncertainty terms and fault-induced perturbations that affect the power unit. Consequently, model inconsistencies and faulty conditions in the functioning of the marine power unit can be diagnosed.