Abstract
KEYWORDS – Magnetorheological Fluids; Multimode Transmission; Hybrid Vehicles, Reduced Viscous Induced Drag Torque; MRF-based Clutch
ABSTRACT – The objective of the project “PHEVplus” is the development of a multimode transmission for Plug-in Hybrid Electric Vehicles. Special feature of this transmission is the integration of Magnetorheological Fluid (MRF) based clutch technologies. In this contribution the main focus is given on the design of advanced MRF-based switch elements (brakes and clutches) by utilizing a magnetically induced fluid movement to reduce drag losses almost to zero. A novel design for MRF-based switch elements is proposed including a serpentine magnetic flux guidance enabling new space saving arrangements. These novel arrangements are theoretically investigated in detail considering leakage flux and certain torque ratios. Since a direct replacement of conventional clutches by MRF-based actuators is hardly possible due to packaging- and weight-requirements a multimode transmission based on a power-split is developed to reduce the torque within the designated clutch components.