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Roy Davis
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In theory, they are "stealing" from the gas tank of everyone who rolls over their device, but what is better: to throw the energy away as heat, or to have it converted to something useful? As paulw says above, they may actually be taking away from his regen braking, but probably not much (and maybe even zero) depending on the type of hybrid system. Seems to me this system would be ideal for interstate tollways like the Pennsylvania Turnpike or around Chicago where you have to slow down to go through the toll gate - save some miniscule wear-and-tear on your brakes and recover energy at the same time. I'd like to see a cost tradeoff study though. The hardware isn't free, and the energy source is sporadic.
JosephT, I believe it is "dissent," and you may be closer to the mark than you think...
... and ... (6) PM motors have a weight (power density) benefit over induction motors, especially when including the inverter, and are generally a few percentage points better in cycle-averaged efficiency. That said, they suffer from worse fault modes and are somewhat more expensive, mainly due to magnet costs and rotor construction. Regards,
A couple of things jump out at me on this article. (1) It is certainly valuable work to find less expensive magnets. (2) Good ac induction design is very competitive with good pm motor design, but in general, pm motors allow for reduced inverter current ratings, when pm motor fault modes are handled well. This translates to a cost savings that can offset the magnet cost. (3) FEA methods have been used for far more than crash and wind tunnel simulations in the auto industry, for decades. (4) Raser is certainly high on hype, if not all hype - its motors are no better than other good IMs. Last time I checked even their website videos were 2nd rate. (5) Frankbank's comments on cycle-averaged efficiency are dead on. A peak number may be good for advertising, but not much else. Regards,
Alex, I'm not as familiar with motorcycle dynamics as I am with light duty vehicles, but I would suspect that the torque capability of the HEV motor is not high enough to provide all the braking, regardless of front or rear wheel drive, especially at only 2.5 kW power level. Hence, it is likely that all possible regen is captured with the RWD scooter. A hub motor, generally being a higher torque motor, MAY be able to offer better regen, but not guaranteed. There's no indication here of the Ah capacity of the battery, or peak power capability, so you may not even be able to capture more regen. Regards,
I would suggest that Ford/Magna, should they produce what they promise with the C-platform (Focus or Focus-like) EV in 2010, at the promised "affordable" price, will dominate Tesla and Mitsu.