Robustness evaluation of real-time fuzzy logic control of the VGT and EGR on a diesel engine

Real-time fuzzy logic controllers (RFLC) have been developed for the VGT and EGR control on a heavy-duty diesel engine. Previous studies show that compared to the VGT and EGR controlled by conventional PID controllers, there is a increase of engine torque and a reduction of engine emissions when the engine is running on the same condition. This work carried out robustness evaluation of the RFLC control using the 1D transient engine model built in AVL-BOOST simulation platform. The evaluation includes a sudden air leak test and a turbocharger mechanical efficiency deterioration test. Simulation results show that the fuzzy logic controller is able to make necessary adjustments in both tests. It is able to compensate for the inlet pressure and flow loss either due to the air leak or the efficiency drop without losing engine torque and producing excessive increase of the soot and NOx.