Schaeffler China Plug-In P2 Hybrid DCT Concept Car
by Dipl.-Ing. Bertrand Pennec
This paper describes the implementation of a plug-in hybrid powertrain into an existing mass production conventional Chinese car. The resulting demonstrator vehicle, the “Schaeffler China Concept Car” (SCCC) combines a 3-cylinder 1.0 L combustion engine (ICE), a 6-speed dry Dual Clutch Transmission (DCT) and the highly modular Schaeffler P2 Hybrid System.
This cost efficient hybrid solution, relying on a single electric motor (eMotor), was installed in front/transverse arrangement.
In particular, the engine and transmission of the original vehicle were fully replaced by the combination of the downsized engine and the P2-Hybrid-DCT. The obtained powertrain was mechanically and functionally integrated thanks to a worldwide collaboration between Schaeffler and Continental as well as the vehicle manufacturer. In addition to the mechatronic expertise demonstrated in the scope of this project, all technologies deployed in the SCCC are ready for mass production.
Associated to the P2 Hybrid Module, the drive strategy plays a core role to guarantee the overall vehicle drivability and powertrain efficiency. The prototype hybrid control unit (HCU) and the related master control software were developed by Schaeffler Engineering. The HCU provides 5 different driving modes, each offering a different vehicle experience to the driver.
Especially, next to usual functions like torque distribution, gear strategy, energy management, the HCU governs a quick and smooth combustion engine restart process via the K0 dry disconnection clutch of the P2 module instead of the classical pinion starter.
Illustrated by simulation results and measurements, the paper will present the evaluation of the drivability performance and fuel economy behavior of the prototype vehicle.
The generic, reusable HCU software architecture, its main functionalities and development process will be explained in the later context of this paper.