Abstract
One of the promising methods which improve fuel economy of hybrid electric vehicles is to increase the regenerating power. We focused on changing the powertrain layout of hybrid electric vehicles and control strategy of the regenerated power until lower vehicle speed at deceleration. In this study, fuel economy and exhaust-gas emission characteristics of hybrid trucks were investigated by using the Hybrid powertrain test bed system with modifying the hybrid power- train layout and the hybrid control methods. As the regenerated power was increased, fuel economy and exhaust-gas emission were improved at the engine-out (upstream of exhaust-gas aftertreatment devices). On the other hand, exhaust -gas emission from the tailpipe (downstream of the devices) showed no relationship with the regenerating power.
