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On the heels of the BMW X6 ActiveHybrid, BMW announced the production
version of the all-new BMW 7 ActiveHybrid, which will also premiere at
the 2009 Frankfurt Auto Show (IAA). The BMW 7 ActiveHybrid will reach
America shores in Spring, 2010. 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 elec¬tric motor gives
the BMW 7 ActiveHybrid a combined output of 455 hp and maximum torque of
516 lb-ft (preliminary figures). 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
(preliminary), while delivering fuel economy approximately 15% better
than the 750i. Official EPA ratings will be available closer to the US
market launch.
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: A key element of the
BMW EfficientDynamics philosophy.
The BMW 7 ActiveHybrid takes an innovative approach to ensure
outstanding efficiency in this segment. At the same time this unique
sport sedan offers dynamic driving characteristics at a level that one
would expect from The Ultimate Driving Machine. BMW ActiveHybrid is an
important element within the BMW EfficientDynamics philosophy meant to
offer technologies able to significantly reduce fuel consumption and
emissions on every new model while enhancing driving performance.
BMW uses hybrid technology because it can make an effective contribution
to the reduction of fuel consumption and emissions. As a rule, the
savings potential of hybrid technology increases with the power of the
combustion engine interacting with the system. In the case of the BMW 7
ActiveHybrid precise coordination of the electric motor and the V8
serves to optimize the efficiency of the combustion engine under all
operating conditions.
Intelligent energy management for
generation, storage and use of electric power.
The ActiveHybrid concept stores energy in a compact, high-performance
lithium-ion battery. The processes of charging the battery, supplying
power to the electric motor, and electric ancillaries are managed by a
control unit developed specifi¬cally for the BMW 7 ActiveHybrid.
Energy Regeneration: Electric power
captured using no extra fuel.
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.
Two interconnected on-board networks for
flexible management of energy.
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.
Cutting-edge battery technology:
lithium-ion with superior capacity and multi-cycle operating strength.
BMW found that lithium-ion battery technology offers sufficient energy
storage capability while taking up minimal space. The result is that the
BMW 7 ActiveHybrid gives up almost no luggage capacity to its
conventional siblings (750i and 750Li), because the 120-volt battery is
small enough to be mounted underneath the trunk floor. Furthermore, the
weight penalty incurred by this battery is minimal, meaning less energy
is consumed to carry it. Using this technology enables the ActiveHybrid
7 to maximize storage capacity and acceleration in the hybrid luxury
sedan segment. It is the fastest-accelerating hybrid sedan in the world.
The useful energy provided by this high-performance battery is 400
watt-hours. The battery itself is comprised of 35 cells and an
integrated control unit which continuously analyzes the charge level and
ensures appropriate dependability under all conditions. Despite its high
level of performance, the lithium-ion battery measures just 14.6 x 8.7 x
9.1 inches (37 x 22 x 23 centimeters) and weighs a mere 59.5 lb or 27
kg.
Hence, it is only slightly larger than a conventional car battery and is
housed conveniently in the trunk floor between the wheel arches of BMW 7
ActiveHybrid, safely surrounded by a high-strength special casing. This
location provides protection for the battery and helps to preserve the
7-Series' ideal 50-50 weight distribution. The luggage compartment with
its capacity of approximately 13 cu. ft. offers adequate space for four
46-inch golf bags.
Twin-turbocharged V8 gasoline engine
with High Precision Direct Injection.
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.
Displacing 4.4 liters, this outstanding engine delivers its maximum
output of 440 hp between 5,500 and 6,000 rpm. Peak torque of 475 lb-ft
is maintained from 2,000 to 4,500 rpm, with High Precision Direct
Injection ensuring precise supply of fuel at all times. Piezo-injectors
positioned in the combustion chambers between the valves ensure a
smooth, efficient and clean combustion process. The engine fulfils the
European EU5 standard as well as the ULEV II standards in the US.
Compared with the engine featured in the BMW 750i/Li, this version has
been modified in numerous respects to the specific requirements of the
BMW 7 ActiveHybrid. There is no starter, alternator, or belt drive for
the air-conditioning compressor and hydraulic pump. The cooling system
has been modified for hybrid operation. The result is remarkable power
from idle. The response of the engine is enhanced by the electric motor
with its additional torque. The direct response to the accelerator pedal
is impressive when compared either with conventional 7-Series models or
existing hybrid vehicles already in the market. Acceleration to 60 mph
in 4.8 seconds (preliminary) ranks it among the fastest and most
thoroughbred sports cars in the world. Top speed of BMW 7 ActiveHybrid
is electronically limited to 150 mph.
Electric motor starting and supporting
one of the most advanced V8s.
The three-phase synchronous electric motor featured in BMW 7
ActiveHybrid is positioned between the engine and the torque converter,
and is connected to the crankshaft. Shaped like a disc, the electric
motor weighs 50.7 lb (23 kg). Its compact design ensures full
integration in the transmission housing.
The electric motor generates boost of approximately 20 hp and peak
torque of 155 lb-ft. When operating as a generator in Brake Energy
Regeneration, the electric motor produces approximately 27 hp of brake
force.
In total, the BMW 7 ActiveHybrid features a maximum system output of 455
hp and peak torque of 516 lb-ft (preliminary). Normally, this level of
power output would require a correspondingly high increase in fuel
consumption. The BMW 7 ActiveHybrid, in contrast, combines its power
with an equally impressive increase in fuel efficiency of about 15%.
8-speed automatic transmission in
combination with Auto Start Stop.
To transmit the drive power developed jointly by the V8 and the electric
motor, the BMW 7 ActiveHybrid features a newly developed 8-speed
automatic transmission specifically tailored to the demands of hybrid
technology. This high-tech transmission combines shift comfort,
sportiness and efficiency at unprecedented levels.
The new 8-speed close-ratio automatic transmission uses an inno¬vative
gear-set configuration providing two additional gears and a larger
overall gear range than the 6-speed automatic transmission used by BMW
without negative effects on size, weight, or internal efficiency. With
the new transmission, the V8 engine is better able to stay in the power
peak while ensuring greater overall efficiency.
Overall efficiency is further enhanced with the Auto Start Stop
function. Auto Start Stop automatically switches off the combustion
engine at idle, eliminating fuel consumption when stopped. Once the
driver's foot comes off the brake pedal, the engine restarts
instantaneously.
Starting of the V8 engine is accomplished by the electric motor, which
is supplied with power from the high-voltage battery. This enables the
engine to start extremely quickly and without any vibration. The
automatic transmission is maintained in a "ready-to-drive" mode by a new
hydraulic pressure accumulator for the valve body of the transmission.
Additionally, the engine control unit "remembers" engine crank position
and uses delay-free ignition to restart the engine in less than one
crank rotation. The engine is also switched off when the driver uses the
Auto Hold function. The driver just has to slightly press down on the
gas pedal in order to reactivate the engine.
Continuous climate control in all
circumstances.
The climate control system in the BMW 7 ActiveHybrid is supplied with
power directly from the high-voltage battery, thus ensuring all the
usual functionality regardless of whether the engine is running.
Hence, operation of Auto Start Stop does not compromise the infotainment
or climate system operation. The desired interior temperatures are
maintained consistently, regardless of how frequently or for how long
the engine shuts off.
The standard 4-zone automatic climate control has a parked-vehicle
function activated whenever desired by remote control. This feature
serves to cool down the interior in hot weather before getting into in
the car. The highly efficient air conditioning system can reduce in
interior tem¬perature quickly and efficiently by more than 50 degrees
Fahrenheit, providing pleasant starting conditions in an appropriately
cool and pleasant passenger compartment. By running on pure electric
power, the air conditioner compressor begins cooling the car more
quickly than in a conventional system.
Efficiency made visible: special display
concept.
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.
Using the iDrive control system in the Central Display, the driver is
able to see a detailed view of the interaction between the V8 engine and
electric motor. Beyond the current charge level of the lithium-ion
battery, this display also shows the real-time flow of energy. As an
alternative to this graphic display, the system can analyze the current
efficiency. In this case a bar graph, which is updated every minute,
shows the efficiency levels achieved by the hybrid components during the
last fifteen minutes.
Cutting-edge suspension technology for
maximum control and comfort.
When the new BMW 7-Series was introduced in 2009, it set new standards
for comfort and driving dynamics. The double-wishbone front suspension
and an enhanced Integral-V rear suspension provide the ActiveHybrid 7
with the ride comfort one would expect of a BMW sport-luxury sedan with
the handling and control of a sports car.
The long-wheelbase version of BMW 7 ActiveHybrid includes self-leveling
rear suspension. Both models are fitted with BMW's vehicle
speed-variable Servotronic power steering as well as Driving Dynamics
Control. The driver is able to choose the preferred shock absorber
setting, the appropriate operation of Dynamic Stability Control, the
shift character of the automatic transmission, as well as the throttle
response and Servotronic steering assist.
The brake system on the BMW 7 ActiveHybrid provides excellent stopping
power in every situation. Inner-vented discs and floating calipers front
and rear guarantee resistance to fade. The ActiveHybrid 7 comes standard
with 19-inch light-alloy rims in an aerodynamically optimized ten-spoke
Aero turbine wheel design, unique to this model. Likewise, runflat tires
measuring 245/45 R19 front and 275/40 R19 rear enable the driver to
continue even after a complete loss of pressure at a speed of up to 50
mph for up to 150 miles. As an added measure of security, the Tire
Pressure Monitor will warn the driver if ever the pressure in any of the
tires drops more than 20 percent.
ActiveHybrid safety systems.
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.
Best of Hybrid: flexible development for
optimized concepts on each model.
The hybrid components featured in BMW 7 ActiveHybrid were developed
jointly by BMW and Daimler in a cooperation project seeking to develop
and test components for hybrid drive in luxury performance cars. Apart
from the electric motor and the lithium-ion battery, this joint venture
also served to develop the power electronics for the high-voltage
network featured in the BMW 7 ActiveHybrid.
Each manufacturer subsequently integrated the hybrid components into the
respective model in accordance with individual, brand-specific
requirements. One of the unique characteristics of the BMW 7
ActiveHybrid is exemplified by the combination of an electric motor with
a V8 engine.
BMW ActiveHybrid is based on a modular principle which, following the
Best of Hybrid strategy, ensures perfect integration of the optimum
component in vari¬ous vehicle concepts. Hence, the mild hybrid concept
of the BMW 7 ActiveHybrid is tailored ideally to the specific
requirements of this model as is the full hybrid concept for BMW X6
ActiveHybrid, which will arrive at BMW Centers in late 2009.
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