BMW X6 ActiveHybrid
BMW announced the production version of the BMW X6 ActiveHybrid. The BMW X6 ActiveHybrid makes its world premiere at the 2009 Frankfurt Motor Show (IAA) and will reach US BMW Centers in fourth-quarter 2009. ActiveHybrid technology provides a glimpse into the future, achieving outstanding driving dynamics with equally impressive efficiency. It melds both of these qualities to offer a truly unique driving experience. The world's first Sports Activity Coupe with full hybrid drive capitalizes on the options offered by combining the combustion engine with electric motors to create a powertrain with new levels dynamic performance and efficiency.
BMW ActiveHybrid technology offers a significant increase in driving dynamics and at the same time reduces fuel consumption by approximately 20 percent versus a comparable vehicle powered by a combustion engine alone. The result is even greater driving pleasure combined with enhanced fuel economy and CO2 management providing the kind of progress to make the BMW X6 ActiveHybrid a genuine BMW in the hybrid market.
The overall drive system featured in the BMW X6 ActiveHybrid consists of a 400 hp twin-turbocharged V8 gasoline engine and two electric synchronous motors delivering 91 hp and 86 hp, respectively. Maximum system output is 480 hp, and peak torque reaches 575 lb-ft.
Precisely controlled interaction of the three power units optimizes the overall efficiency of the BMW X6 ActiveHybrid at all speeds, with acceleration from a standstill to 60 mph in 5.4 seconds. Top speed of the BMW X6 ActiveHybrid is limited electronically to 130 mph, with average fuel consumption in the EU test cycle improved by roughly 20%, and a CO2 emission rating of 231 grams per kilometer. EPA ratings will be available closer to the market introduction.
BMW's first full hybrid model is able to run exclusively on electric power - and that is entirely free of CO2 - up to a speed of 37 mph (60 km/h), with the combustion engine being activated automatically whenever required.
These performance figures are made possible by utilizing a two-mode active transmission. The ideal combination of the two power modes can be controlled for enhanced efficiency and dynamic performance in any driving condition. With the two electric motors, three planetary gearsets and four multi-plate clutches, drive power is transmitted through a 7-speed automatic transmission. As would be expected in a BMW, the driver can operate the transmission manually. BMW's lauded xDrive all-wheel-drive system distributes the power between the front and rear axles.
The electric motors receive their energy from an NiMH high-performance battery pack positioned beneath the floor of the luggage compartment. This battery pack also feeds electric power to the vehicle's on-board network. Luggage compartment capacity is therefore the same as on the original BMW X6. On brake application and/or on deceleration, kinetic energy is converted into electrical energy and is stored in the battery pack. To provide this function either one or both of the electric motors act as a generator, feeding electric power generated back into the high-voltage battery.
The combustion engine is the innovative reverse-flow V8 first featured in the BMW X6 xDrive50i. 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 400 hp between 5,500 and 6,400 rpm. Peak torque of 450 lb-ft is maintained from 1,750 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 fulfills the European EU5 standard as well as the ULEV II standards in the US.
Compared with the engine featured in the BMW X6 xDrive50i, this version has been modified in numerous respects to the specific requirements of the BMW X6 ActiveHybrid. There is no starter, alternator, or belt drive for the air-conditioning compressor and hydraulic pump. The dual-circuit cooling system has been modified for all-electric operation.
The sporty driving behavior of the BMW X6 ActiveHybrid is due largely to BMW's xDrive all-wheel-drive system. Electronically controlled, variable distribution of drive power front-to-rear gives the BMW X6 ActiveHybrid superior traction and enhanced driving dynamics.
xDrive features smooth division of drive power through a transfer case with an electronically controlled multiple-plate clutch that feeds power to the axle with optimum wheel contact and grip on the road. Under normal conditions BMW xDrive distributes drive power to the front and rear axle in a 40:60 split. Sensors constantly measure wheel slip at both the front and rear, and varies the balance of drive power within a fraction of a second. Unlike conventional all-wheel-drive systems, xDrive "looks ahead" and does not only respond when a wheel has already begun to spin.
he BMW X6 ActiveHybrid is the first Sports Activity Vehicle to feature Electronic Power Steering. This allows variable steering assistance both when driving with the combustion engine and in the all-electric mode.
Electronic Power Steering on the BMW X6 ActiveHybrid comes complete with fully integrated speed-related Servotronic steering assistance. Servotronic reduces assistance at high speeds ensuring not only directional stability but also extremely precise steering behavior in corner. At low speeds, on the other hand, for example when parking, extra power assistance significantly reduces the steering forces required.
The BMW X6 ActiveHybrid is equipped with a new generation of Auto Start Stop technology, specifically tailored to the requirements of a hybrid vehicle. Auto Start Stop functions at all ambient temperatures. While the engine is switched off, the electric air-conditioning compressor automatically maintains the climate and temperature desired within the passenger compartment. All other electrically operated functions continue uninterrupted, with the on-board network supplied with power from the battery pack. The hybrid Auto Start Stop can be deactivated by choosing the Manual gearshift mode on the automatic transmission.
Intelligent lightweight construction and a special body structure for maximum rigidity also characterize the unibody of the BMW X6 ActiveHybrid.
The BMW X6 ActiveHybrid comes with three-point inertia-reel seat belts for all seats featuring belt force limiters and belt pretensioners on the front seats. To protect the occupants from cervical spine injury in the event of a collision at the rear, the front seats feature crash-activated headrests, the rear seats come as standard with ISOFIX child seat fastenings. The vehicle is equipped with frontal and hip thorax airbags, and side-curtain head airbags.
All restraint systems are controlled by central safety electronics including rollover sensors. The system can activate the side-curtain airbags and belt pretensioners in the event of an impending rollover.
Standard adaptive bi-xenon headlights ensure optimum illumination of the road ahead by steering with the vehicle. A daytime running light function operates through the corona rings. The BMW X6 ActiveHybrid also features a windshield-mounted sensor that automatically controls the lights and windshield wipers on demand. Additional comfort at night is provided by available Automatic High Beams which will automatically dim the high beam headlights when an oncoming vehicle is detected. The standard Head-Up Display projects information relevant to the driver onto the windscreen.
Source: BMW press