(continued from the previous page)
Drivetrain
The 2.0 TFSI in the
Audi Q5 Hybrid quattro has a displacement of 1984 cc. Its output is 211
hp, with the maximum torque of 258 lb-ft (350 Nm) permanently available
between 1,500 and 4,200 rpm. The four-cylinder unit combines gasoline direct
injection with turbocharging.
The 2.0 TFSI has been overhauled in
some respects for use in the Audi Q5 Hybrid. The drive of the ancillary units
has been dropped, and the crankshaft bearing and fine tuning of the turbocharger
have been adapted to the specific demands. A secondary air system at the
cylinder head makes sure that the exhaust gas treatment cuts in particularly
fast. Integrated in the engine control unit, the so-called hybrid manager
controls the efficient change and smooth transitions between the operating
modes.
A largely modified eight-speed tiptronic serves as the power
transmission without the aid of a torque converter. Its place is taken by the
disk-shaped electric motor, combined with a multi-plate clutch bathed in oil,
which couples and decouples the electric motor and the TFSI. The innovative
decoupler operates precisely and smoothly in any situation.
Electric Motor
The radiator tank in the engine bay houses the
power electronics. The so-called pulse-controlled inverter serves as a
controller between the battery, which outputs direct current, and the electric
motor that operates on alternating current. Innovative technologies keep the
volume and weight of the power electronics low, with cooling provided by a
separate low-temperature water-filled circuit. The component includes a DC/DC
converter that couples the electric consumers in the 12 V electrical system with
the high-voltage network.
A permanently excited synchronous machine
serves as an electric motor, as a starter and - during deceleration - as an
alternator. It delivers up to 54 hp (40 kW) of power and 156 lb-ft (210 Nm)
of torque. The electric motor is integrated in the engine's cooling circuit.
Performance and
Fuel Consumption
The 2.0 TFSI and the electric motor of the Audi Q5
Hybrid are mounted directly behind one another as a parallel hybrid system - a
straight-line concept with impressive efficiency. Together they have a system
output of 245 hp and a system torque of 354 lb-ft (480 Nm). The Audi Q5 Hybrid
sprints from 0 to 60 mph in 7.0 seconds. The propulsion ends at no less than 138
mph (222 km/h).
In the normal cycle, the Audi Q5 Hybrid quattro consumes 6.9 liters of fuel
per 100 km. The 75-liter (19.81-US gallon) tank yields an impressive
range comparable to that of a TDI.
Lithium-Ion Battery System
A lithium-ion battery system, weighing merely 84 lbs
(38 kg),
serves as the energy store for the electric motor of the Audi Q5 Hybrid quattro.
The compact unit with its 6.87 US-gallon (26-liter) capacity is positioned in a
crash-safe area under the loading floor, with hardly any detriment to the
luggage compartment. The battery consists of 72 cells; at 266 volts its nominal
energy is 1.3 kWh and its output 39 kW.
The lithium-ion battery is cooled
by air in two ways, depending on the requirement. At low-temperature load, it
draws temperate air from the vehicle interior by way of a fan. If its
temperature exceeds a certain limit, a separate refrigerant circuit is
activated. It is coupled to the main climate control system of the vehicle and
uses a separate evaporator. This efficient, active cooling mechanism is a major
factor in the hybrid system's high electric availability and sets the Audi
Q5 Hybrid quattro apart from many other hybrid vehicles.
Operating Modes
The Audi Q5 Hybrid quattro can be driven in five operating modes. Driving with
the combustion engine alone, with the electric drive alone or in hybrid mode is
possible, as are recuperation and boosting. At a standstill - before starting or
at a traffic light, for instance - both drive sources are deactivated. In this "comfort" start-stop mode, the climate control system remains active. Once the
driver releases the brake, the Q5 Hybrid quattro begins coasting. It can be
driven up to 62 mph (100 km/h) under electric power - with almost no noise or
local emissions. At a constant speed of 40 mph (60 km/h), it has a range of 2
miles (3
km) - enough for many residential areas and city centers.
The driver can
change between three programs using a button on the center console or the
selector lever. The EV characteristic map gives priority to the electric drive
in the city, the D mode controls both motors for optimal consumption, and the S
mode as well as the touch control gate of the tiptronic are designed for a
sporty driving style.
If the driver accelerates quickly, the combustion
engine takes over and delivers traction. Now the electric motor's main job is to
power the on-board consumers and keep the accumulator battery charged. In quick
acceleration, or "boosting," the electric motor operates together with the TFSI;
at full throttle in the S mode the full system output is briefly available. In
such cases, the hybrid drive supplies the propulsion power of a large naturally
aspirated engine, but with far more efficiency.
When the driver releases
the accelerator, the electric motor acts as an alternator and recovers energy.
In most situations the TFSI is then decoupled from the drive system so as not to
cause any drag losses. The electricity recovered by the electric motor here and
in braking is buffered in the lithium-ion battery. If the driver brakes only
slightly, the electric motor performs the deceleration by itself; in more
forceful braking the hydraulic braking system is simultaneously activated.
Quattro Drive and Chassis
Quattro permanent four-wheel
drive reliably applies the power of both power units to the road in any
situation. In the normal condition the sporty drive is emphasized at the rear;
if need be, it transmits most of the power to the axle with the better traction.
The sophisticated chassis includes many aluminum components for reduced weight.
The Audi Q5 Hybrid quattro is capable of pulling trailer loads of up to 4,409
lbs
(2000 kg).
The steering is based on an electromechanical system. The
system is extremely efficient because it consumes no energy when driving
straight ahead. The brake servo is additionally supplied by an electric vacuum
pump. A complex control strategy adapts the braking to the conditions of
electric driving and energy recuperation.
Equipment and Trim
The
climate control system in the Audi Q5 Hybrid is adapted to the requirements of
electric driving. A high-voltage electric drive was used for the compressor. It
operates on-demand, making it highly efficient. An electric auxiliary heater
ensures that the cabin heats up quickly.
The Audi Q5 Hybrid quattro
offers virtually the same equipment as its successful sibling models - the model
series leads the European market in the mid-sized SUV segment. The options also
include the advanced Audi driver assistance systems.
A new feature is
Internet connectivity via the optional Bluetooth car phone online. A UMTS model
connects to special services from Google and the World Wide Web, allowing the
car to retrieve the latest news and weather information. Through the fast
connection the hybrid SUV also downloads three-dimensional satellite images and
aerial photos from Google Earth. These appear in a bird's eye view on the
monitor, and the computer fills in the roads. Another high-end feature is the
WLAN hotspot, which allows passenger to connect up to eight terminal devices to
the Internet.
Note: the equipment, data and prices specified in this document
refer to the model range offered in Germany.
Audi Q5 Hybrid: Photo Gallery, Review (1/2) and Specifications