SKF announced today it has recently developed a benchmark rotor positioning bearing (RPB) design, in collaboration with a leading belt-driven starter/generator (BSG) manufacturer. The company has augmented its RPB range with a new and compact design that is suitable for all belt-driven starter/generator applications in both 12V and upcoming 48V formats.
BSG is the preferred architecture for mild hybrid electric vehicle powertrain designs, which provides a low-cost solution to reduce fuel consumptions and CO2 emissions. The unit enables fast stop/start, regenerative braking and boosting functions. The electronic control unit (ECU) of the BSG requires instantaneous detection of rotor position and/or speed in order to work efficiently. The most reliable and economical way to achieve this is to mount an RPB combined with a sensor directly integrated in the ECU, noted SKF.
SKF said that as the hybrid electric vehicle market is set to grow rapidly, newcomers are beginning to address the corresponding growth in demand for BSGs. It is gearing up to supply this market with a new universal RPB design that is both axially-compact and robustly-constructed, and is also easily integrated into current and future BSG designs.
The RPB of SKF has an envelope (encompassing both bearing and magnetic ring) which is similar to that of a standalone bearing. It can be easily fit onto the BSG shaft’s existing bearing location, adjacent to the ECU, noted the company. Since the magnetic ring is mounted on top of the bearing outer ring, the axial length of the BSG is not badly impacted by sensor integration compared to a standard alternator, it explained.