Somewhere in England: After test runs in the U.K. the commercial-drive-powered e=motion will attempt the electric vehicle land speed record this month.
With a boost from commercially available power conversion equipment, an odd-looking British car may soon blaze into the record books as the fastest electric vehicle ever.
Dubbed e=motion, the missile-shaped vehicle measures 33 feet long and weighs 1.6 tons. Inside the car are four packs of lead-acid batteries that produce 600V dc. An ACS600 ac drive produced by ABB Ltd (www.abb.com) converts this output and supplies two 40 kW ABB IP23 ac motors driving the wheels of the vehicle.
This power package is supposed to propel e=motion to speeds in excess of 249 mph, the current electric land speed record. In tests, the car has already reached 196 mph, much faster than the U.K. record speed for such a vehicle.
While building e=motion, designers Colin Fallows and Mark Newby decided to stick with components that were basically off the shelf. "We wanted to prove that two ordinary English guys can go out and purchase the stuff to break the record," says Fallows.
To set an official world record, e=motion must make two runs clocked at better than 252 mph. So the car needed a high-speed motor like the ABB unit, which operates at 5,000-9,000 rpm. To prevent overheating at high speeds, each motor includes a 24V dc fan for forced ventilation.
On the downside, the motors "came up a little bit heavier than we would have liked," Fallows notes. But they provide "excessive power" that compensates for any small weight disadvantage, he adds.
For precise control of motor torque, the ACS600 features ABB's Direct Torque Control (DTC) algorithm. DTC "forms an accurate software model of the motor," explains Frank Griffith, an ABB drives specialist who worked with e=motion's designers.
With this accurate model, the controller can operate a motor very close to its maximum power capacity for short periods of time. In the case of e=motion, Griffith says, the motors can be overloaded to approximately 180-200 kW (up to five times their rated value) for about five minutes. "That allows them to put high levels of torque on the road wheels to accelerate the vehicle," he adds.
This month, e=motion will be transported to the Chott el Jerid salt flats in the Tunisian Sahara. There, if all goes according to plan, the ABB motor/drive combination will help e=motion reach a scorching speed of 310 mph. Fallows is "very confident" that the record will fall. "We're going to blitz it," he says.