A Fault-Tolerant Soft/Hard Hybrid Control for Fault Diagnosis of Aero-engine Sensors

In this brief paper, a fault-tolerant soft/hard hybrid control scheme based on the Kalman filter is proposed for fault diagnosis of aero-engine sensors. The designed soft fault diagnosis system, in particular, can detect whether a fault exists by residual processing sensor measurement values and a set of Kalman filter estimation values and summing their weighted squares to compare the known thresholds. In addition, to determine whether there is a fault, the developed hard fault diagnosis system compares the residual absolute value of the sensor measurement value and the estimated value of a Kalman filter with the known threshold value. Finally, some numerical simulations of the fault of the low-pressure rotor speed sensor of an aero-engine are performed to validate the proposed method's feasibility and fault tolerance.