Audi has fallen behind its rivals when it comes to electric cars but the automaker is out to rectify the issue with the launch of its first all-electric model next year. Audi is now saying it’s started work on a premium sedan with very large batteries. The car has even been confirmed by Audi’s head of development, Prof. Dr. Ulrich Hackenberg.
This new Audi is being designed as a premium sedan to rival the Tesla Model S which is making waves. Audi will use the technology being developed for the R8 e-tron to give their car at least 450km range. With a total of 280 kW and 820 Nm available virtually from off, the electric motors give the Audi R8 e-tron impressive performance. They catapult it from 0 to 100 km/h in 4.2 seconds, and top speed is limited to 200 km/h. In the test-bench cycle, one battery charge is sufficient for driving over 215 kilometers.
The electric motors achieve over 95 percent efficiency over a wide range; ungoverned, they could rev up to 12,500 rpm, which would make them capable of a speed of more than 250 km/h. Designed as permanently excited synchronous machines, they deliver a high performance and torque density and can also run efficiently on a small amount of electricity. The stator temperature is controlled by a water jacket, and the air additionally cooled by an air flow. The single-stage planetary gears are incorporated into the cooling circuit.
Each electric motor is supplied by separate power electronics, which are likewise temperature-controlled. The pulse inverters that convert the battery’s direct-current voltage into alternating-current voltage redefine the benchmark for compact, lightweight design. The driveline’s control concept has designed-in redundancy and satisfies the highest possible safety standards – the controllers of the power electronics communicate with each other and with the drive controllers.
The chassis of the Audi R8 e-tron, too, features new solutions. The coil springs are made from glass-fiber-reinforced polymer (GFRP) and weigh only 1.2 and 1.3 kilograms respectively, about 40 percent less than steel springs. The rear wheel hubs are of forged titanium, saving 0.6 kilograms of weight. For the anti-roll bar at the front, wound layers of CFRP form the tube, and the shanks are made from aluminum – the component weighs just 2.5 kilograms, a saving of 35 percent.
