Improvement of Transient Operation Controllability in Engine Test Bench for Heavy-Duty Vehicles

In this study, two kinds of control methods for the transient operation of an engine test bench for heavy-duty vehicles were applied in the JE05 test cycle and World Harmonized Transient Cycle (WHTC) test conditions in order to evaluate the controllability of transient operations and the effect on emissions. One control method uses dynamometer torque with its inertia correction as the feedback signal (dyno torque F/B control); the other method uses axial torque measured by a flange-type high-response torque meter as the feedback signal (axial torque F/B control). The transient operation controllability using the axial torque F/B control improved compared with the dyno torque F/B control. The results influence NOx emissions in the emissions test cycle, such as JE05 and WHTC, with the engine test bench. Axial torque F/B control could become a more useful technique when it is required to improve the reproducibility of real driving conditions.