Actuator Fault Diagnosis with Application to a Diesel Engine Testbed

This work addresses the issues of actuator fault detection and isolation for diesel engines. We are particularly interested in faults affecting the exhaust gas recirculation (EGR) and the variable geometry turbocharger (VGT) actuator valves. A bank of observer-based residuals is designed using a nonlinear mean value model of diesel engines. Each residual on the proposed scheme is based on a nonlinear unknown input observer and designed to be insensitive to only one fault. By using this scheme, each actuator fault can be easily isolated since only one residual goes to zero while the others do not. A decision algorithm based on multi-CUSUM is used. The performances of the proposed approach are shown through a real application to a Caterpillar 3126b engine

Actuator fault detection and isolation for diesel engines

International audienceThis work addresses the issues of actu- ator fault detection and isolation for diesel engines. We are particularly interested to diagnosis faults af- fecting the Exhaust Gas Recirculation (EGR) and the variable Nozzle Turbine (VNT) actuator valves. To accomplish this goal, a residual generator based on a nonlinear mean value model of the diesel engine is proposed using a bank of observer. Each residual on the proposed scheme is based on a nonlinear unknown input observer and designed to be insensitive to only one fault. By using this kind of scheme, the actuator faults can be easily isolated since only one residual goes to zero while the others do not. A decision al- gorithm based on multi-CUSUM is used. The perfor- mances of the proposed approach are shown through the application to a diesel engine model