Fault Diagnosis in Sensors of Boiler Following Control of a Thermal Power Plant

In this paper a system of fault detection and isolation (FDI) in sensors of boiler following control of a thermal power plant is presented. The approach is based on a polytopic quasi-Linear Parameter Variant (q-LPV) model derived from a simplified nonlinear model for the boiler-turbine unit representing the dynamic behavior of the pressure in the first stage of the turbine, drum pressure, superheated steam pressure and electrical power. The nonlinear model is parameterized with real data operation of a thermal power plant, in a wide range of loads (low, medium and high). For residual generation a Luenberger-like observer based on the polytopic q-LPV model is designed. The performance of the FDI system is evaluated adequately by using a simulator in Simulink based on the nonlinear model. The main contribution of this work is to demonstrate that our proposed approach is feasible to be applied in a real thermal power plant.