In search of driving pleasure: quattro drive and suspension :

quattro and e-tron – that is the perfect combination for powerful performance and high efficiency. In the Audi e-tron1, the brand with the four rings introduced a new generation of quattro drive in 2018: electric all-wheel drive. In conjunction with the versatile suspension, the low center of gravity and the powerful electric motors, the electric SUV offers optimum traction, outstanding dynamics and unshakable stability on any terrain and in any weather – enormous driving pleasure in short.

Variable torque distribution: the electric all-wheel drive

With the electric all-wheel drive Audi transferred the combined know-how from more than four decades of quattro drive into the electric age. The premium brand combined the efficiency of a single- axle drive with the driving dynamics and traction of an all-wheel drive. This technology also reached a new level of variability, dynamics and precision.

The electric motors are the ideal power source for the high-precision, ultrafast quattro drive in the Audi e-tron1: The drive torque can be controlled instantly and distributed fully variably between both axles in fractions of a second – constantly tailored to the particular driving situation. In conjunction with the wheel-selective torque control, the electric all-wheel drive offers high traction in all weather conditions and on any surface. The dynamic talents of the Audi e-tron1 are especially apparent at low coefficients of friction, such as on snow.

In most cases, the electric SUV tends to use its rear electric motor to achieve the highest efficiency. For reasons of efficiency, the drive torque is generally distributed with a rear-axle bias. If the driver demands more power than the rear electric motor can supply, the electric all-wheel drive redistributes torque as required to the front axle. This also happens predictively even before slip occurs in icy conditions or when cornering fast, or if the car understeers or oversteers. It takes just 30 milliseconds or so from the system detecting the driving situation and the torque from the electric motors kicking in – much faster than with conventional quattro technology. The reason is that with the electric all-wheel drive a mechanical clutch is not engaged but electricity is simply distributed. And that is almost instantaneous with absolute precision. So even with sudden changes in the coefficients of friction and extreme driving situations the full quattro performance is guaranteed.

Intelligent connectivity: cooperation between control units

Thanks to the many years of experience and quattro expertise Audi has developed all the main software components and their connectivity in-house. Numerous control units work together closely in the Audi e-tron1 and coordinate all functions for the powertrain.

First and foremost is the drive control unit. It controls the distribution of the drive torque between the two electric motors, with the emphasis always on the optimum performance and, in turn, high efficiency. In addition to the state of charge and the temperature of the high-voltage battery and electric motors, the drive control unit also takes into account the selected drive range and the power requirement. For instance in drive range S with activation of the kickdown, the boost power of 300 kW is released to deliver maximum performance. In accordance with the required torque of the drive control unit, the power electronics incorporated in the electric drive supply the electric motors with power.

The central control unit for the suspension is the electronic chassis platform (ECP). For the first time, it integrates the driving dynamics control of the quattro drive, i.e. the all-wheel controller, as well as the wheel-selective torque control. The control is much quicker and much more precise thanks to this integration. In situations where handling dynamics are relevant such as understeer or oversteer, the electronic all-wheel controller overrides the specified torque distribution of the drive control unit. From data such as steering angle, engine torque, transverse and longitudinal acceleration it calculates the ideal torque distribution for the particular driving situation. If oversteer is imminent, more torque is sent to the front axle to pull the Audi e-tron1 out of the bend. The driver can thus accelerate in the bend early into the next straight and needs to intervene less to make corrections. Tracking stability is enhanced. The all-wheel controller decides on the basis of each situation whether it adjusts the engine torque or increases the brake intervention – and does so individually on each axle. That contributes to the agile handling of the Audi e-tron1 and makes for a sporty basic setup, particularly in terms of transverse dynamics. If there are signs of understeer with a sporty driving style, in other words the vehicle moves across the front axle, the all-wheel controller activates the hydraulic wheel brakes to distribute torque laterally and directly controls the brakes individually. This wheel-selective torque control gently brakes the wheels with reduced load on the inside of the curve, thus increasing the drive power to the wheels on the outside of the curve with the higher wheel load. This difference turns the car into the bend, allowing the car to follow the steering angle. The upshot: precise, neutral handling coupled with enhanced dynamic cornering.

Innovative traction control in the Electronic Stabilization Control (ESC) also delivers high traction and vehicle safety. Thanks to innovative networking and shifting of functional modules from the ESC to the power electronics, the wheel slip is now controlled at millisecond intervals. As such, it can be adjusted precisely to the driving situation and the road surface condition. The result is improved acceleration and enhanced stability on snow and ice. In conjunction with the all-wheel controller the new traction control delivers optimum grip between tire and road surface. The drive control unit coordinates the traction control and the all-wheel controller.

Wide-ranging character: Audi drive select

The Audi e-tron’s1 characteristics can be adjusted via the standard Audi drive select dynamic handling system across seven profiles – from overtly comfortable, through extra-efficient, to distinctively sporty – according to the driving situation, road condition or personal requirements. Apart from the auto, comfort and dynamic modes, the driver can also choose from the efficiency, individual, allroad and offroad programs. They permanently influence the steering assistance, the drive characteristics and the air adaptive suspension with controlled damping. If the driver selects the dynamic mode in Audi drive select, the drive range S is active automatically and in turn also the boost mode. Here, the drive produces 300 kW and delivers 664 Nm (489.7 lb-ft) of torque. The efficiency mode moves the powertrain, the climate control and the standard-fit cruise control or the optional adaptive cruise control to a more economical basic setting and thus assists the driver with a driving style that optimizes fuel economy. In individual mode the driver can configure the setup based on their personal wishes. The driver adjusts the settings of the required drive mode via the button in the switch strip in front of or in the MMI.