LA Auto Show Preview: 2011 Audi Q5 Hybrid Quattro

Audi has released the first details of the 2011 Audi Q5 Hybrid Quattro ahead of its unveiling at the Los Angeles Auto Show.

Like the A8 Hybrid concept unveiled at 2010 Geneva Motor Show, power is provided by a 155 kW (211 PS / 208 hp) 2.0-liter TFSI gasoline engine and a 33 kW (45 PS / 44 hp) electric motor.

Producing a combined 180 kW (245 PS / 241 hp) and 480 Nm (354 lb-ft) of torque, the Audi Q5 Hybrid accelerates from 0-100 km/h in 7.1 seconds and has a top speed of 222 km/h (138 mph). Furthermore, the Audi Q5 Hybrid can run on electricity-alone but only up to 3 km (1.9 miles).

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.

The consumption by the Audi Q5 hybrid quattro lies under 7.0 liters per 100 km (33.60 US mpg) in the normal cycle – that corresponds to a CO2 emission of less than 160 g/km (257.50 g/mile). The 75 liter (19.81 US gallon) tank yields a reliable range comparable to that of a TDI.

The Audi Q5 hybrid quattro will arrive at dealerships during 2011.

The Drive
The 2.0 TFSI in the Audi Q5 hybrid quattro has a displacement of 1984 cc (121.08 cu in). Its output is 155 kW (211 hp), with the maximum torque of 350 Nm (258.15 lb-ft) permanently available at 1500 to 4200 rpm. The 4-cylinder engine combines direct injection with turbocharging – typical for the Audi philosophy of downsizing, which replaces displacement by charging. The Audi valve lift system (AVS) further increases power, torque and efficiency by switching the stroke of the exhaust valves between two stages depending on the load and rpm.

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, and was fully developed by Audi alone.

A largely modified eight-speed tiptronic serves the power transmission without the aid of a torque converter. Its place is taken by the disk-shaped electric motor, combined with the multi-plate clutch operating in an oil bath – it couples and decouples the electric motor and the TFSI. The innovative decoupler operates with high precision, smoothly and quickly in any situation.

The highly comfortable and fast-shifting hybrid gear unit contributes significantly to the efficiency of the Audi Q5 hybrid – its eight gears are widely spaced. When the 2.0 TFSI is turned off, an electric pump maintains the oil pressure in the hydraulic system to safeguard the convenient start-stop feature.

The Power Electronics and the Electric Motor
The power electronics, connected to the battery and the electric motor by high-voltage cabling, is located in the plenum chamber of the engine compartment. In the form of a so-called pulse-controlled inverter, the power electronics 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 so-called permanently excited synchronous machine serves as an electric motor, as a starter and – during deceleration – as a generator. It outputs up to 33 kW (45 hp) of power and 211 Nm (155.63 lb-ft). The electric motor is integrated in the cooling circuit of the engine.