Automotive Intelligence - the web for automotive professionals and car enthusiasts
September 25, 2008
Implementation of such technologies in a luxury performance saloon of this calibre leads to a new perception of hybrid technology as such: In the configuration developed by BMW hybrid technology ensures a significant increase in efficiency without in any way giving up the high standard of driving dynamics, motoring safety and comfort so typical of the brand.
The drivetrain of the BMW Concept 7 Series ActiveHybrid is made up of a V8 gasoline engine with Twin Turbo and High Precision Injection based on the power unit of the BMW 750i. Maximum output of the conventional engine in the regular production model is 300 kW/407 hp, with peak torque of 600 Newton-metres or 442 lb-ft.
Now this superior engine is combined with an electric motor fully integrated in the transmission housing, developing maximum output of 15 kW/20 hp and peak torque of 210 Newton-metres/155 lb-ft. So with the mild hybrid concept, the electric motor boosts the dynamic driving potential of the eight-cylinder gasoline engine in a unique manner most appropriate for the character of the BMW 7 Series, giving the car even more dynamic acceleration.
Using Brake Energy Regeneration, the electric motor supplies electric power to the power-consuming items on board the car, minimizing the direct conversion of fuel into electrical energy and maximising the drive power available for enhanced driving dynamics.
The hybrid components developed for the Concept Car are based on technology created by BMW and Daimler in their cooperation on hybrid drive systems. In this joint venture the two manufacturers have successfully developed components for hybrid drive including the power electronics and high-voltage batteries. Naturally, the hybrid drive system featured by BMW offers all the characteristics and highlights typical of the brand.
The compact electric motor integrated in the transmission housing replaces the conventional alternator driven by the engine as well as the starter. Electrical energy is generated through Brake Energy Regeneration with a unique degree of effi ciency and without in any way impairing the drive power of the engine itself. Integrated power electronics, in turn, ensure compact design within dimensions never seen before, as well as safe and secure arrangement of all hybrid components.
A high-performance lithium-ion battery integrated in the luggage compartment in accordance with the package of the car saves the energy generated and supplies power to the on-board network. Through its high storage capacity, the battery makes full use of Brake Energy Regeneration with its particular potential.
Thanks to the higher degree of electric power provided in this way, additional functions in the car are run completely under the electric power supply. The Auto Start Stop function preventing the combustion engine from running in the idle mode is particularly helpful and comfort-oriented in this case thanks to the combination with ActiveHybrid technology.
(Sept 24, 2008)