BMW 7-Series ActiveHybrid
The BMW 7 ActiveHybrid is based on the newest BMW 7-Series. This unique car sets new standards for performance and efficiency in the premium luxury class.
This symbiosis of an upgraded twin-turbo, High Precision Direct Injection, V8 engine with a 3-phase synchronous electronic motor gives the BMW 7 ActiveHybrid a combined output of 455 hp and maximum torque of 516 lb-ft. Power is transmitted via an 8-speed automatic transmission with the electric motor positioned between the engine and the torque converter. The electric motor receives its supply of energy from a lithium-ion battery developed specifically for use in this automobile.
Precisely controlled interaction of both power sources serves to maximize the efficiency and dynamic performance of the BMW 7 ActiveHybrid. The result is a unique driving experience that demonstrates the performance capabilities of modern hybrid technology. The BMW 7 ActiveHybrid accelerates to 60 mph in 4.8 seconds, while delivering fuel economy approximately 15% better than the 750i.
BMW ActiveHybrid technology also provides new features that promote efficiency while preserving comfort. As an example, the BMW 7 ActiveHybrid is the first BMW with automatic transmission to feature Auto Start Stop to maximize efficiency by avoiding engine idling when stopped. Another advantage is that the air conditioning and ventilation system remains fully operational when using Auto Start Stop. In this case, power is supplied directly through the 120-volt on-board network powered by the lithium-ion battery.
Special displays in the instrument cluster and the Central Display inform the passengers of the degree of efficiency and the current operating status of the hybrid components. The ActiveHybrid 7 is distinguished from the 750i by aerodynamically-tuned ten-spoke 19-inch light-alloy Aero wheels, and model designations on the trunk lid, C-pillars, and on the door cutouts. The BMW 7 ActiveHybrid is also available in Bluewater Metallic exterior paintwork.
Like existing BMW 7-Series models, BMW's first luxury sedan with ActiveHybrid technology will enter the market in two body variants. The extended version of BMW 7 ActiveHybrid has a wheelbase increased by 5.5", all of which is devoted to the enhanced comfort of rear-seat passengers. Both models are available with a wide range of options from the portfolio of equipment and accessories offered on the BMW 7-Series, enabling the tailoring of the ActiveHybrid 7 to individual tastes and requirements.
BMW ActiveHybrid technology uses energy that would be normally converted into heat through the brakes, and therefore wasted in conventional cars. The BMW 7 ActiveHybrid features an enhanced version of Brake Energy Regeneration already used in some current BMW models running on a combustion engine alone. In this case the integrated electric motor acts as a generator when coasting or applying the brakes, in order to feed electric power into the battery. Brake Energy Regeneration converts some of the vehicle's kinetic energy into electric power for the on-board network whenever the driver lifts off the accelerator or applies the brakes. On acceleration, electricity is fed back into the on-board network from the lithium-ion battery. This sequence relieves the combustion engine from the task of converting some of its fuel energy into electric current, and thus enables the engine to provide more power directly to the rear wheels. The result is better acceleration even than the 750i, despite the fact that the additional power is obtained in a way that does not require additional consumption of fuel.
When the driver requires only a small amount of brake force, the system uses only the drag of the electric generator (motor). The mechanical brakes are activated only when the driver presses down the brake pedal harder for more stopping power. Dynamic Stability Control controls the balance of electrical and mechanical braking so adeptly that the driver does not even perceive the transition from braking with electric power to braking with the mechanical brake system.
The BMW 7 ActiveHybrid features both a conventional 12-volt on-board network fed by an absorbent glass mat (AGM) battery and an additional battery featuring lithium-ion technology operating at 120-volts. The lithium-ion battery supplies power to the electric motor as required and serves to start the engine. Electric power generated by Brake Energy Regeneration is fed into both on-board networks. The air conditioner compressor on BMW 7 ActiveHybrid is integrated in the 120-volt network. All other electrically operated functions of the car are supplied by the 12-volt network. The two on-board networks are connected by a voltage converter featuring flexible energy management. Both batteries are charged and maintained through Brake Energy Regeneration. The 12-volt battery is fed with energy from the high-voltage network.
The combustion engine is the innovative reverse-flow V8 introduced in the BMW X6. The world's first V8 gasoline engine with two turbochargers in the V-section between the two rows of cylinders develops power throughout the entire engine speed range. The spontaneous and direct response of this engine results from its compact configuration, which allows the shortest exhaust manifolds.
Featuring Black Panel technology, the instrument cluster in the BMW 7 ActiveHybrid is supplemented by an energy flow display in the lower section of the tachometer, a blue arrow shows the current status of Brake Energy Regeneration. When accelerating, an additional graphic display illustrates the boost effect generated by the electric motor.
The safety concept for the car's hybrid components is comprehensive. All components in the high-voltage system feature full insulation and special plug connectors. The lithium-ion battery is protected by a high-strength steel housing and is positioned between the wheel wells in the luggage compartment, and has already been subjected to a wide range of crash tests. Last but not least, the entire high-voltage system is automatically switched off within a fraction of a second in case of a malfunction or collision.
Source: BMW press