Fuel consumption and pollutant emissions always play a large role in the development
of new engine generations. Next to further fuel consumption optimizations for diesel
engines, the development of efficient and clean gasoline engines is increasingly
becoming the focus of vehicle manufacturers.
Promising starting points for reducing fuel consumption are, for example, the reduction
of the displacement and a reduction in the number of cylinders in the combustion
engine, which is also known as downsizing. The loss of power and driving comfort
resulting in the use of smaller displacement engines as compared to the power and
driving comfort of its higher capacity brothers, in particular the lack of torque
in the lower RPM ranges, need to be compensated for through the use of a suitable,
powerful charging system. In addition to turbochargers with variable turbines or
regulates 2-stage turbocharging systems (R2S™), electrically assisted charging systems
are increasing being viewed as a possible solution.
As the leader in technology in the field of charging systems, BorgWarner Turbo Systems
has emphatically pushed for the development of the innovative eBooster concept.
This electrically assisted charging system uses a flow compressor driven by an electric
motor placed as a component before or after the turbocharger. In contrast to electrically
assisted turbochargers, this system works with two stages, i.e. like two turbo-machines
connected in series. In doing so, the pressures of the two charging units are multiplied.
Through the use of two perfectly matched flow compressors it is possible to optimally
adapt the entire system to the particular purpose and expand its entire power curve.
eBoosters and exhaust turbochargers are also separate units. This has the distinct
advantage that, when suitably positioned, the thermomechanical stress on the electrical
and electronic components is significantly less than with electrically assisted
The eBooster permits the development of small and efficient high-performance turbocharged
engines whose dynamic response matches that of large non-supercharged engines of
the same output class. The superiority of the eBooster was impressively demonstrated
in close cooperation with various customers for gasoline engines as well as for