Amazing 400mph or bust: Meet the VBB-3, the world’s fastest electric car This electric record machine is built by students at the Ohio State University.






The Venturi eye Buckeye Bullet-3 combines two things we love here at be9ja: land speed records and electric vehicles. It's a collaboration between Venturi—a Monegasque electric car company—and the Ohio State University that aims to break 400mph (644km/h) on the Bonneville salt flats while simultaneously acting as a testbed for future electric vehicles and the young engineers who work on it. Fortunately Columbus, Ohio, is less than a day's drive from Washington, DC, so I took advantage and paid the land speed car a visit.

VBB-3—its nickname—is the third land speed car to come from the Center for Automotive Research (CAR) in Columbus. Its long, thin shape has been dictated by aerodynamics, unencumbered by the draggy intakes required to feed air-breathing engines. It has a pair of electric motors, each good for 1,500 horsepower (1,119kW) and powered by eight large lithium-ion battery packs. Earlier VBBs set records in 2009 and 2010, but last summer terrible salt conditions prevented VBB-3 from running a proper test program to 400mph and beyond.

Each axle is powered by its own electric motor. The starting point is the same EV motor Venturi builds for its sports cars, running here at a much higher voltage. In fact, there are actually two EV motors in each unit. "It's two motors sharing a cooling system and a common shaft," team leader (and former graduate student) David Cooke told us. "It makes more manufacturing sense to build smaller motors and couple them together than trying to build one big motor. Today that motor is putting out about 1,000 horsepower in the dyno, but it's capable of 1,500." The team is continuing to develop the powertrain—particularly the inverter control—to give VBB-3 the 3,000hp it needs.

"Motor technology is already there," Cooke said. "The real limit is where you get the energy from." For VBB-3, that means lithium-ion battery packs from A123 (VBB-2 used hydrogen fuel cells). The team—engineering students at OSU, remember—did the rest, integrating them in the powertrain, cooling them, and so on. There's a total of eight battery packs on the car, four on either side of the carbon fiber cockpit tub (enjoying a new life after retiring from its previous career as a Dallara IR03 IndyCar).

Two battery packs are bussed together and fed into each inverter, the hardware for which is supplied by American Traction Systems. The inverters just look like large metal boxes ahead or behind the wheels, but they convert DC from the batteries into the AC needed by the motors.

Keeping the motors cool enough during the car's minute-long runs is crucial. "The real limit to how hard you can push the motors is ensuring you don't exceed the temperature limits of the magnets and electrical windings and insulation," Cooke said. "These motors have oil cooling jackets over the stator, and we also pump oil over the magnets for the best possible cooling."

Radiators would mean vents or intakes, which would in turn mean drag. Therefore VBB-3 has closed-loop cooling systems instead. "We have a water tank we pack full of ice and prechill as much as humanly possible before the race," Cooke explained. (That's all in one big aluminum housing up front.) "This year we also developed an off-board cooling loop for the motors so we have an ATF [automatic transmission fluid] oil chilling circuit that circulates around the motors. We get the motors and inverters down to about 0 degrees Celsius before the start of a run, and they're at operating temperature in around 60 seconds."

The gearbox—a two-speed—is custom made by Hewland in the UK. "The amount of torque the motors put out—and how quickly they can do it—requires some special things from the transmission. By that point, with a really custom solution we were able to do all the other things we wanted," Cooke said. One of those was hanging the suspensions from the gearbox casing, something you usually see on prototype or open-wheel race cars. "Another neat system we've developed is a fullfull



With carbon fiber relegated to the bodywork, the focus was back on a metal tube frame. Cooke said the design team didn't want to just settle for conventional off-the-shelf 4130 steel, however. None of the more exotic alternatives proved superior. "The maximum weight saving was about 50 lbs, but cost goes through the roof, weldability goes down, and in most of those metals vibration fatigue is terrible," he said. Using aluminum would mean inspecting the frame after every second run to check for fatigue. Magnesium would have been very light but with an incredibly complex welding process. "We're in the middle of the desert, and if there are things we need to fix, it's hard to beat steel tubing."

VBB-3's design has to take into account a much harsher environment than all the other race cars and bikes built by the students at CAR. Corrosion isn't a problem at the salt flats themselves, but it surely is after spending a couple of weeks there. "One year we hadn't had time to paint the chassis before Bonneville, so we knew we'd have to strip it when we got back. It was covered in salt and water so we power washed it in Utah, and it was beautiful new metal; we got as far as Iowa on I-80 and everything just turned orange—it was like an explosion," Cooke told us.

Titanium and aluminum are used where appropriate, and Cooke and his team have been exploring advanced coatings for other parts. They work closely with a coatings group in Dayton that does aerospace work, for example, and when visiting we saw a brake system being machined that was destined to be sent away for an advanced nickel coating. "In most cases there are things out there [for a given application], you just get down to practicalities of can we/should we do that," Cooke says.

Over the winter every nut and bolt comes off the car. "Everything is a prototype system, so we really have to watch everything we can. We'll inspect the entire chassis, do some non-destructive testing on the welds looking for cracks, we'll pull all the battery pack parts apart," Cooke told us. "This year at the race track we saw the most vibration that I think any land speed car has ever seen." Indeed, VBB-3 was the only car to be timed on the Bonneville salt flats in 2015, a consequence of storms that wrecked the surface for speed runs. "By the time we were racing it was dry, but there were soft pockets just underneath the salt. The surface was blowing up like little land mines."

In 2015, VBB-3's pilot, Roger Schroer, was at least officially timed at 288mph (463km/h). On his final run, he continued accelerating to almost 300mph (482km/h). VBB-3 ended the day bleeding its crimson coolant onto the salt, the extremely bumpy track resulting in a punctured coolant tank. "In general, vibration isn't an issue; if you're going to do 400mph you expect a smoothed, polished course," Cooke said. "We felt 300 was the limit this year." Schroer told the team the ride felt like what it must have been like to take off in a rocket; the vibration was so severe he couldn't focus on the marker flags that lined the course.

Even if it didn't reach 400mph, Cooke told us that the team still learned a lot last year. "Every 25mph is a new boundary. We increase speed in 25 to 50mph increments so you can look at the data; is the car lifting, are the tires right, is the aerodynamics right?"

In that light, knocking on the door of 300mph was a big milestone even if the result is not quite as fast as VBB-2.5. "Yes we've been there with previous cars, but this is an all-new car, all-new systems," Cooke said. "I wish we had a bit more time this year with a better track."

We all hope that 2016 grants Cooke and the rest of the VBB-3 that wish. If so, don't be surprised if there's another 25 to 50mph increment or two to study.




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