Fault-Tolerant Internal Model Control of a Diesel Engine Air Path

The paper considers the fault-tolerant control of the boost pressure and the exhaust gas recirculation of a two-stage turbocharged Diesel engine air path. The aim is to recover the stability and setpoint tracking properties of the closed-loop system in case of actuator, sensor or system faults. A model of the nominal air path is extended to describe the Diesel engine under the influence of the faults and to apply the principle of Fault-Tolerant Internal Model Control (FTIMC). The application study compares the FTIMC scheme with the nominal Internal Model Control of the Diesel engine and shows that for several important fault cases the FTIMC principle recovers the stability of the control loop and leads to severe improvements of setpoint tracking properties.