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BMW Active Hybrid: X3 EfficientDynamics |
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Higher Performance, Lower Emissions.
Driving calculations based on the BMW Concept X3 EfficientDynamics serving as
a high-tech development vehicle confirm the great advantages BMW’s concept
offers the driver: These calculations show that the car accelerates much faster
than a comparable production vehicle of the same kind with conventional drive,
the BMW Concept X3 EfficientDynamics accelerating according to calculations in
approximately 6.7 seconds from 0–100 km/h and reaching a top speed of approximately
235 km/h or 146 mph.
This superior performance comes with a further reduction of fuel consumption and,
accordingly, emissions in the European driving cycle by approximately 20 per cent.
Intelligent management of the flow of energy, therefore, lifts those virtues so
typical of BMW to a new, even more fuel-efficient pinnacle.
Engine Technology Both Dynamic and Economical All in One: Six-Cylinders
with Jet-Guided Direct Gasoline Injection.
This synthesis of economy, ecology and driving pleasure is made possible by the
intelligent combination of the combustion engine and the electric motor. The main
source of power, reflecting an old and proven BMW tradition, is of course the
straight-six BMW engine in its most advanced and sophisticated configuration:
a gasoline power unit with High Precision Injection, that is jet-guided direct
gasoline injection ensuring a significant increase in efficiency on higher torque
and power over the current generation of power units. And indeed, jet-guided direct
gasoline injection is not the only special feature, since the six-cylinder will
be the first engine completely
without V-belts, ancillaries such as the steering servo pump, the brake servo
and the air conditioning compressor being driven by their own electric motors.
The electrical power generator in the Active Transmission, finally, takes over
the conventional functions of the alternator.
The Big Advantage of the Electric Motor: Superior Torque Right from the Start.
Additional use of an electric motor allows the utilisation of specific physical
benefits: Although an all-electric drive system is inferior to a combustion drive
principle, the electric motor nevertheless offers interesting features in conjunction
with the combustion engine: While the combustion engine, due to its inherent system
and underlying technology, is able to develop torque only as of a certain minimum
speed, the electric motor generates its full torque right from the start, that
is from a standstill. A further advantage is that the electric motor develops
a relatively high level of torque even at low power, making the electric motor
the right kind of drive technology for setting off smoothly and directly, while
the combustion engine always requires a clutch to bridge the difference in engine
speed to the wheels initially at a standstill before setting off.
With increasing engine speed, the output of both drive systems increases a long
and almost linear curve. The only drawback is that the electric motor required
to develop more power also requires a correspondingly greater energy supply, where
the weight of batteries or fuel cells quickly reaches practical limits and restrictions.
So with BMW’s system the torque generated by the electric motor decreases
on an over-proportional curve as soon as the electric motor has reached maximum
output when accelerating.
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BMW contract hire
