How do you feel about wheel hub motors for conversions?Practical or not?
They sound like a wonderful thing, but I haven’t seen any in person or found them for sale. Mostly you find them featured on futuristic concept cars or motorcycles. Have you found someone selling them?
I suspect the challenge would be integrating regular braking with the motor (even with regen you need mechanical braking), so you’d probably need to buy a complete wheel package tailored for your vehicle.
The next challenge is controlling the motors. Most EVs use a single motor and controller combo. With wheel-hub motors you’d have at least two, maybe all four wheels running an independent motor. Having a controller which is intelligent about monitoring individual traction and power demands will be needed.
That all points to a fair bit of complexity and fail-safe systems, which means higher cost. On the other hand I bet it would make a sweet EV!
Over in the UK we have prototype vehicles with Motor-in-hub systems that control multiple drive wheels. We have a 55 seater AWD EV “Bendy Bus” which The City of Edinburgh requested a client of ours cost following a three year trial with the original single engined EV Think City car from Norway. This trial was initiated while Th!nk was still owned by FoMoCo and the city thought that road pricing revenues could fund a fleet of these. [See http://www.guptapartnership.com/up_frame.html for that Edinburgh case study]
In the UK there is also an articulated EV Truck and a self drive, small four-seater PSV both using the same motor in wheel system controlled by a master computer. The huge benefit here is that you can do away with the engineering complexity, piece cost and the weight of the diff and gears, drive train etc which yield higher operating efficiency in terms of range, speed and battery charge life. And yes, I have driven them and the AWD means they are at home on slippery conditions, be it wet leaves or snow, even with the Bendy Bus!
There are also systems which use ICE’s to replenish battery power for EV’s so you overcome the range issue that has limited EV performance to date. Right now most of this progress is still under wraps but it is just a matter of time before these systems hit the road. Now when they do, a lot of the complexity of the hydrogen solution may be less relevant. You have to think of the next generations of EV’s more as computers with wheels rather than your current mental image of the conventional ICE car. Different aspects will make them sexy. For one, they are near silent, so stealth versus exhaust note! You can track comparisons on many current pure EV’s at this website: – http://www.mygreenwheels.com/