Modular P2-P3 Dedicated Hybrid Transmission for 48V and HV applications

Oerlikon Graziano has designed and patented an elegant DHT concept, starting from the know-how cumulated in the last years from the concept of the OGeco transmission, previously presented at the CTI Berlin. This has been achieved by continuous improvement activities ongoing on the demo vehicle and focusing on the market needs. The transmission is a modular concept which starts from a traditional 2-shaft single-clutch transmission. Thanks to a link between two main gears of the gearbox and the direct gearing between the electric machine and this linked gear arrangement, free-mounted on the primary shaft, the concept allows a very efficient electric path of the transmission, which presents two different gear ratios between the electric machine and the secondary shaft. The solution is particularly innovative, because keeping a very simple and well known architecture (therefore cost effective), it allows the connections to be made with standard transmission components, selectively coupling the electric machine to either the primary or the secondary shaft. This feature, then, represents a mixed P2-P3 hybrid architecture and therefore takes the advantages of both (e.g. powershifting-P3, recuperation-P3, cranking-P2, standstill charging-P2). It allows a performance increase of up to 40% on 0-100 kph and up to 25% benefit on CO2 emission, with a charge-sustaining strategy for the battery, with the installed electric power being 30% of the total. Thanks to its scalability and to the possibility of having different power-split configurations the system can be used both as a mild-hybrid or as a plug-in hybrid solution, within a 48V or HV system.