Integrated powertrain control applied to AMT designs for improved shift quality, efficiency and other characteristics using novel hardware and sensors

摘要

The following aspects of twin-path AMT performance are considered: · CO{sub}2 efficiency through improved powerpack design and control · sustained clutch slip capability through improved powerpack design · shift quality and characterisation through improved algorithms and sensor technology A hierarchical control structure is assumed for overall integration of powertrain elements. In this supervisory/co-ordinated scheme, the transmission is considered as a module comprising the dynamic model of the hardware and a local control element. It has authority to request control of external torque sources (engine only in this case) during the shift to achieve the desired shift quality whilst modulating internal components such as clutches. The transmission module is able to perform clutch modulation and control of input torque during the shift process to achieve either a speed or torque profile during the various stages of torque-matching and synchronisation. The work also investigated the relative benefits of speed and practical torque sensors to achieve optimum shifts and imparting desirable character to an optimally smooth shift. Novel design features such as dual-driven, electro-mechanical pump systems are discussed to overcome the limitations of current systems. Where presented, results are derived from co-simulation of Matlab/Simulink and Boeing's EASY5. The paper finds: · the efficiency of the transmission and sustained-slip performance may be improved through the use of clutched, dual-drive electro-mechanical pump systems with a high pressure accumulator. Results are shown for the MVEG drive cycle: 2.7 % CO{sub}2 reduction for a conservative estimate of the three designs considered in comparison with a mechanically driven, fixed displacement system. · electrical generation of cooling flow in a wet qiutch design is shown to allow sustained hill-hold on a 20% gradient. · equivalent or improved shift quality may be achieved between a current automatic and a twin clutch AMT. When fitted with an output torque sensor and subject to fully integrated powertrain control, shift character can be accurately controlled. · a variety of new topics for AMT development are presented.