A Multiple Model-Based Approach for Fault Diagnosis of Jet Engines

In this brief, a novel real-time fault detection and isolation (FDI) scheme that is based on the concept of multiple model is proposed for aircraft jet engines. A modular and a hierarchical architecture is developed which enables the detection and isolation of both single faults as well as multiple concurrent faults in the jet engine. The nonlinear dynamics of a dual spool jet engine is linearized and a set of linear models corresponding to various operating modes of the jet engine (namely healthy and different faulty modes) at each operating point is obtained. Using the multiple model approach the probabilities corresponding to each operating point of the jet engine are generated and the current operating mode of the system is detected based on evaluating the maximum probability criteria. It is shown that the proposed methodology is also robust to the failure of pressure and temperature sensors and extensive levels of noise outliers in the sensor measurements. Simulation results are presented that demonstrate the effectiveness and capabilities of our proposed multiple model FDI algorithm for both structural faults and an actuator fault in the aircraft jet engine.