Browse Publications Technical Papers 2000-01-0519
2000-03-06

Evaluation of Turbocharger Power Assist System Using Optimal Control Techniques 2000-01-0519

In the paper we employ numerical optimal control techniques to define the best transient operating strategy for a turbocharger power assist system (TPAS). A TPAS is any device capable of bi-directional energy transfer to the turbocharger shaft and energy storage. When applied to turbocharged diesel engines, the TPAS results in significant reduction of the turbo-lag. The optimum transient strategy is capable of improving the vehicle acceleration performance with no deterioration in smoke emissions. These benefits can be attained even if the net energy contribution by the TPAS during the acceleration interval is zero, i.e., all energy is re-generated and returned back to the energy storage by the end of the acceleration interval. At the same time the total fuel consumption during the acceleration interval may be reduced. These results are compared to the “conventional” vehicle (without TPAS) and to the case when the supplemental energy is applied directly to or taken directly from the crankshaft as in a parallel hybrid vehicle configuration. Comparison with the conventional vehicle and with the parallel hybrid vehicle reveals the mechanism by which TPAS can reduce pumping losses at the initial phase of acceleration thereby improving fuel economy.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 43% off list price.
Login to see discount.
Special Offer: Purchase more aerospace standards and aerospace material specifications and save! AeroPaks off a customized subscription plan that lets you pay for just the documents that you need, when you need them.
X