VW introduced this month the most technically innovative “VW” since the brand has been in existence. Their new Touareg will also be the first and only off-roader in Europe by a German car maker to be available in a hybrid version. It sets standards among fully off-road capable SUVs with petrol engines that have a fuel consumption value of just 8.2 liters fuel per 100 kms.

The dashboard of the Touareg Hybrid also sports the familiar screen display where you can see the continuous "interplay" of engine, batteries and electric motor to achieve optimal power and economy... 

The Touareg Hybrid can also be driven up to 50 km/h in purely electric mode. Among the diesel engines, the Touareg V6 TDI with 7.4 litre combined fuel consumption now posts the best value in the segment of – as the factory puts it – “genuine” SUVs. Suffice to say that the Touareg is an important car. Not less than 500.000 Touaregs ofr the previous model have been sold so far…

Orange coloured CAN Bus lines run from the hybrid power controller to the High Tension battery... giving away that this cas is also driven by electric power...  

Hybrid technology from VW…

We will look more closely here at the hybrid setup VW has engineered for their Touareg. Key components of the Touareg Hybrid powertrain − equipped with a high-voltage battery − are its supercharged V6 TSI (petrol direct injection engine with 245 kW /333 PS), 8-speed automatic transmission − ideally suited for hybrid and towing duty − and the hybrid module that is integrated between the internal combustion engine and the automatic transmission. This compact module with disengagement clutch weighs only 55 kilograms. This module is located downstream of the V6 TSI, and it integrates the disengagement clutch and E-Motor (34 kW/47 PS) in one housing.

When the V6 TSI and E-Motor work simultaneously (boosting), a total power of up to 279 kW /380 PS is generated with a maximum torque of 580 Newton-meter as measured – to put it in VW factory language - on the dynamometer.

…is a parallel hybrid drive setup

Volkswagen has chosen a parallel hybrid drive configuration for the Touareg. This layout has the advantage over other potential hybrid systems, that it assures excellent off-road performance and unlimited continuous climbing ability. With a maximum trailer payload of up to 3.5 tonnes, the Touareg is an excellent towing vehicle even in the hybrid version. Moreover, the parallel hybrid is more efficient than alternative hybrid concepts on long-distance and (high speed) freeway journeys.

It is no sluggard either: still according to the factory, The Touareg Hybrid reaches a maximum speed of 240 km/h and accelerates to 100 km/h in just 6.5 seconds. Of course, the emphasis is on economy: the hybrid concept delivers over 25 percent fuel savings in city driving, In combined mode driving – a mix of city, highway and freeway drives – development engineers calculate an average saving of 17 percent.

The high voltage battery is located in the back, two cooling fans maintain proper temperature...

Essentially, four driving modes are used to achieve this fuel efficiency on the Touareg Hybrid:

Driving only on the “E-Motor”: Electric, emission-free driving (up to 50 km/h) reduces petrol consumption. In this mode, the V6 TSI is not only shut off, but is also disengaged from the 8-speed automatic by a disengagement clutch to avoid drag torque losses.

A more detailed view of the high voltage battery with two cooling fans dismantled to show the internals...

Coasting: As soon as the driver releases the accelerator pedal, the V6 TSI is disengaged from the transmission. This is even possible at higher speeds (up to 160 km/h), i.e. on the open road and “autobahn” as well. The Touareg “rolls” significantly longer, since drag torque losses are eliminated. When you adopt an anticipatory driving style, the positive impact on fuel economy is clearly felt. One comes to the conclusion that also with a “normal” car, it is therefore more economical to disengage the clutch and coast with the engine ticking over than to stay in gear, as drag torque losses are greater than the fuel the engine consumes when idling… one is often told otherwise!

Regenerative Braking: During braking, the E-Motor starts operating as a generator and recovers kinetic energy, which is then stored in the high voltage battery (NiMH battery).

Stop-Start System: The Stop-Start system is integrated in the powertrain and improves fuel economy, especially in urban areas and stop-and-go traffic.

A well managed “Interplay” of components

The interplay of components is “directed” by a hybrid manager. This multi-functional unit is integrated in the engine controller and communicates via the CAN bus lines with units such as the automatic transmission, high voltage battery and so-called power electronics that control the electric motor. The latter also manages the energy flow between the electric motor and battery. Using the DC/DC converter, the power electronics also ensures that the car’s 12V electrical system is supplied via the E-motor or the high voltage battery.

Depending on the charge state of the battery (capacity: 6 Ah), vehicle speed and other vehicle-specific parameters, the hybrid manager automatically selects the ideal operating mode based on lightning fast analysis of all signals.

The new Touareg breathes the now familiar "design-DNA"...  

The Nickel metal hydride battery in detail…

The nickel metal-hydride battery used in the Touareg Hybrid reflects what is currently the best and most practical electric storage system for automobiles. Functional safety, robustness and cost are all factors that favor the high-performance NiMH battery.

The battery is located in a space saving area. The battery weighs about 67 kilograms, consists of a total of 240 individual cells and therefore generates a voltage of 288 Volt.

An additional duct integrated in the Touareg’s interior ventilation system and two separate fans keep the battery within an optimal temperature range. A battery manager continually monitors battery charge by coordinating data with the hybrid manager integrated in the engine controller.

Special power cables connect the battery to the power electronics – located to the left of the engine in the front of the vehicle – to supply the E-motor with energy or – in the reverse case – to charge the battery by E-motor while it acts as a generator when braking (regenerative braking) or by the V6 TSI (via load point shift).

In the event of a crash, the high voltage battery is protected by what is known as a “Protect Box”. The battery system, which includes the Protect Box, battery and ventilation components, weighs 79 kilograms.

We invite you to take a look at some photos here, and needless to say that we will be looking forward to have a presentation/test drive with this remarkable car…

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