The wheel-mounted engines eliminate the need for transmission and driveshaft, while the conventional brake discs were replaced by engine-controlled brakes. The front-mounted engine has been entirely removed, the whole car, including the 4 motors, being powered by 190 kg batteries recharged while the vehicle is moving or during braking.
“The batteries and super capacitors weigh in the same as the engine and gearbox which was removed. The location of this mass is also precisely the same as the original car, so handling is unaffected,” PML Flightlink described the batteries.
There are three engine configurations available, namely HPD40, HPD35 and HPD30, providing a maximum power of 120kW, 80kW and 40kW respectively.
“As a comparison the power electronics (included inside the wheel) is around 20 times lighter than the lightest currently available alternative! The motor is around 5 times lighter than the closest rival. So we have a 350v 400A continuously rated (0ver 600A peak rating for a few seconds, although this has so far not been used!) system which weighs less than 24kg total,” PML said about the engines.
Similar technology was also used on Volvo ReCharge, a concept first unveiled at the 2007 edition of Frankfurt Auto Show.