Electro-Mechanical Dual Clutch Transmission Implementation of Moving Magnet Linear Actuation concept in a DCT demonstration vehicle

This paper reports the final stages of vehicle-based development activity for Ricardo's direct acting electromagnetic actuation of gears and clutches for a DCT with a target cost of $710 and reduced CO2 relative to VW's DQ200. TRW Conekt have supported two levels of hardware design and manufacture; this analysis and application of generic DCT control s/w are described: Generation 1: Clutch Actuation and gear actuation using Moving Magnet Linear Actuators (MMLA). Rig and vehicle data are presented with associated control s/w. Generation 2: Revised clutch actuation with simplified topology and drastically reduced magnet content were enabled by matching of the clutch spring force/travel characteristic to compliment the actuator. The following are presented for Generation 2: Validated CO2 simulation and NEDC measurement indicating a 1.4% reduction relative to DQ200; Costing relative to VW DQ200 and Getrag 6DCT250; Productionization studies including plastic over-moulding. The project finds: near cost equivalence with a 1.4% CO2 saving relative to DQ200. However, the frequency response of the actuation system may enable significant driveline damping to be achieved using slip control of the clutch allowing potential deletion of the DMF- with a net saving of c.9% of the target cost relative to DQ200. A complimentary mechanical device associated with anti rollback that increases clutch life is also described.