Offering an insight into the possible
design of the forthcoming BMW X6, the Concept X6 opens up another
untapped market segment, the Sports Activity Coupé. The Concept X6 also
showcases ActiveHybrid, the world’s most advanced hybrid technology and
an integral facet of BMW’s EfficientDynamics philosophy.
The introduction of BMW’s ActiveHybrid technology marks the latest
landmark in BMW’s development of hybrid technologies. BMW started work
on electric drivetrain research with the BMW E1 in the late 1980s and
has been working on hybrid technology and its various options for more
than 15 years. Most recently, hybrid technology has been introduced as
an integral part of the BMW EfficientDynamics programme.
Working alongside Global Hybrid
Cooperation partners, General Motors and DaimlerChrysler, the BMW
ActiveHybrid combines two compact, high-performance electric motors
connected to one another by three planetary gear sets, a
fixed-transmission ratio gearbox and a high-performance battery to
deliver benefits over low and high speed ranges. The result is a
reduction in fuel consumption by up to 20 per cent compared with a
comparable BMW running on a combustion engine alone.
The BMW Concept X6 ActiveHybrid can be
driven on electric power only, on the combustion engine alone, or with a
combination of both power units. Depending on driving conditions, the
electric motors can also be used for both accelerating and regenerative
braking. In the case of brake regeneration, the brake forces, created
when coasting and when applying the brakes, supply power to the
high-voltage energy storage unit to provide an increase in electric
power. A similar philosophy has already been seen in BMW’s Brake Energy
Regeneration systems in almost all of today’s BMW model ranges.
When the driver needs all available
performance to accelerate, one of the two electric motors acts as a
generator, converting some of the engine’s power into electrical current
that is subsequently fed to the battery or the second electric motor.
The second electric motor then converts the power coming from the first
electric motor or from the battery back into mechanical power for the
output drive shaft on the transmission.