What Transmission Systems can do for Downsizing and Downspeeding of Powertrains and Cylinder Deactivation

摘要

The reduction of fuel consumption and CO_2 emissions by optimization of the whole powertrain is shown by introducing measures in the transmission system supporting the ICE to operate in areas of better specific consumption. One of the topics is the optimized damper technology for achieving downsizing and high turbocharging pressures along with effective downspeeding. As a result of investigations of cylinder deactivation in engines with different number of cylinders a new approach is introduced for implementing "RCD 1.5" rolling cylinder deactivation for three-cylinder engines to attain 1.5-cylinder operation or "RCD 2.5" for five-cylinder engines. The resultant torsional vibration excitation of 0.75th order in 13 or 1.25th order in 15N5 engine with rolling cylinder deactivation is controlled by the innovative damper technology, which entails a dual mass flywheel with an optimized characteristic and the use of centrifugal pendulum-type absorbers on the secondary DMF mass that are matched to the main excitation order. The fuel economy improvement including optimized cylinder filling by flexible valve control will be more than 6% in NEDC.