The drivetrain technology in the VW I.D. R Pikes Peak

Tue 12th June 2018

The I.D. R Pikes Peak that Romain Dumas will be driving on 24th June 2018 at the “Pikes Peak International Hill Climb” boasts the most sophisticated powertrain ever developed by Volkswagen Motorsport.

Volkswagen’s first fully-electric racing car has two interlinked, integrated lithium-ion battery blocks on board, located to the right and left of the cockpit. They feed energy to two separate high-performance electric engines for the front and rear axles. Together, they provide performance of 500 kW (680 PS). The actual performance level is controlled electronically, depending on the situation on the track. This means that the neutral driving behaviour ideal for a racing car is achieved when accelerating out of a tight turn, for example, as the front wheels also have to transmit steering forces to the track in addition to the drive power. When Romain Dumas depresses the accelerator or brake pedal, the movements are not transmitted by cables, but digitally with e-gas and brake-by-wire, a braking system with electronic signal transmission.

On-board systems generate one fifth of the energy required

The I.D. R Pikes Peak itself produces up to 20 per cent of the electrical energy required for the 19.99-kilometre race. The engines, which otherwise drive the car, function as generators under braking. This recovery process allows them to generate power that flows back to the battery. This procedure also contributes part of the brake performance. A conventional brake system provides the additional deceleration required. The brake-by-wire system in the I.D. R Pikes Peak is the prerequisite for this. “The interplay between recovery and mechanical braking is controlled by electronic systems that the driver does not even notice,” explains Marc-Christian Bertram, Head of Electrics/Electronics at Volkswagen Motorsport.

Volkswagen Motorsport jumped in at the deep end with the drivetrain technology in the I.D. R Pikes Peak. “It was a massive challenge for our whole engineering team. We had no experience of electric drivetrains to call on in a racing context, a very short timeframe of seven months for development, and we were only able to test on the actual route at the end of May,” summarizes Bertram. Some tension will remain in the air until race day, when Dumas races up Pikes Peak in pursuit of a new record in the category for electric vehicles. The current record stands at 8:57.118 minutes.