Friday, August 23, 2013

KLD updates electric motor for 21st-century cars

KLD built this chassis to demonstrate its OneDrive electric motor, battery, and power controller.
Out in a parking lot by the San Francisco Giants' ballpark, KLD CEO Christian Okonsky explains that the basic electric motor, that used by automakers like Tesla in its electric cars, has not changed much in 100 years. Then he shows me a teardown of KLD's electric motor, this one employing radical features such as a stator broken down into multiple, modular components.
Okonsky's chief scientific officer, Ray Caamano, takes over, diving deep into electrical engineering terminology of which I can follow a bit before my brain starts humming the theme song from "Speed Racer." It's heady stuff but it seems to make sense.
KLD has not only developed a new electric motor, but also come up with a battery pack and power control module, tying the whole system together as a drivetrain for electric cars. This approach, developing battery, control, and motor together, is something I've also heard from Tesla engineers. In an electric car, the pieces are just too interdependent to develop separately, then mix and match.
And Okonsky thinks he has something more efficient than Tesla's, or any other automaker's, drivetrain.
To back it up, he says that KLD's electric drive system, called OneDrive, can get the same range from a 3-kilowatt-hour battery pack as other systems get off of a 5-kilowatt-hour pack. Because of this greater efficiency, KLD uses what Okonsky tells me are power cells, rather than energy cells, for the OneDrive battery.
Like Tesla's, KLD's battery pack is made up of 18650-sized lithium ion battery cells, essentially laptop batteries. However, where energy cells are designed for energy density, power cells are designed with low resistance for quick discharge. One advantage of the power cells in an electric-car application is that their lower resistance means they don't heat up as much as energy cells. Heating is a huge problem in electric car batteries, and something Tesla has spent years developing a system to control.
This chassis actually uses two motors coupled together, one driving each rear wheel, with programming that turns them into an electronic differential
KLD's demo chassis, with the OneDrive system, did not require any external cooling mechanism for battery pack or electric motor. And after I had my turn, in line with a few other journalists, to drive the demo chassis recklessly around the parking lot, the battery pack was completely cool to the touch, while the electric motor was only mildly warm.
That motor is another unique component of the OneDrive system.
Rather than an inductive motor, commonly used to drive the wheels in electric vehicles, KLD uses a permanent magnet brushless motor. Caamano has been developing a new kind of electromagnet for the stator, using amorphous metals.
Discovered in 1960, amorphous metals, sometimes called glassy metals, have the odd property of not being able to retain a magnetic field. Touch a typical piece of metal to a powerful magnet, and it will retain enough magnetism to stick to other pieces of metal. Not so with amorphous metals, which will stick to a magnet just fine, but completely lose any magnetism once taken away from the source.
Used as the core metal in the stator components, the release of magnetism after each electric pulse means lower resistance in the motor, leading to better efficiency.
And instead of using a solid ring of electromagnets around the stator, KLD separates them out into components that fit onto the ring like slices of pie. With this architecture, KLD can adjust the number of electromagnets on the stator, giving the motor different power configurations.
KLD's electric motor is also bigger around than any I've seen in an electric car. Like a large gear, the larger diameter rotor means more torque, especially at higher speeds, than smaller motors. As such, the motor can spin more slowly and doesn't need a reduction gear, at least in the demo chassis KLD let me drive. Reduction gears, used in other electric cars, introduce some efficiency loss.
Lacking the deep pockets of a global automaker or the huge investment base of a Tesla, KLD's strategy is not to build cars, or even manufacture the OneDrive electric drivetrain. The company came up with the design and specifications, contracts out building the components, and wants to sell the drivetrain to vehicle manufacturers. Think KLD Inside labels on cars.
KLD built this prototype vehicle, the Kombi City, for client Cenntro Motors.
One of KLD's first clients, Cenntro Motors, will offer a KLD-powered urban utility truck, the Kombi City. The specifications for that vehicle don't sound very impressive -- 45-mile range and 50 mph top speed -- until you consider that it only carries a 6-kilowatt-hour battery pack. By contrast, the Chevy Volt can go 38 miles on a 16-kilowatt-hour battery pack, while the top-trim Tesla Model S uses an 85-kilowatt-hour battery pack to go 265 miles.
There are, of course, many other differences between these vehicles affecting range, such as vehicle weight and aerodynamics, but one telling number is the EPA estimate for mpg equivalent. KLD says Kombi City scores 250 mpge, more than twice the number managed by electric cars from Fiat, Honda, and even Tesla.
The comparison isn't all that fair, considering the Kombi City is a small fleet utility vehicle lacking the safety features and construction of a passenger vehicle, but it may serve as a proof-of-concept.
And if KLD's technology and performance specifications prove true, it could be the much-needed advance, if not breakthrough, that will make electric cars more practical for everyday drivers.

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