Hybrid home conversion with rear hub motors

[blueflame]

Electric scooters have a hub motor.

What about building hub motors that replace the rear rims on a FWD car?

Physically doable could be 7.5KW replacing a 13" rim?

One on each side totals around 15hp.

Batterys and controller in the rear and it could installed in half a day with little attention to existing components, barring controls, power steer and braking. Regen braking easy too. Louvre screens on grill to keep engine warm?

Should reduce running costs....70mpg to 150mpg??

Maybe large hub motors are available?? Or, who has a machining company?

Interchangeable inserts for the variety of wheel nut configurations and offsets.

On scooters power is generally supplied via a fixed center axle. This would be different....

Or, the whole rear wheel assembly could be remade with an electric motor driving a reduction box/rear axle.

Heres something from China: electric axle http://www.alibaba.com/product-gs/51...showimage.html

[Christ]

I posted a link somewhere about a Mini with in-wheel electric motors... it had 600HP, and a relatively long range.

The notable part of the article was that the company was building those motors not just for the Mini, but universally.

[Christ]

Electric Mini: 0-60 in 4 Seconds: It Has Motors In Its Wheels

[MetroMPG]

One challenge of using hub motors in cars is what to do with the mechanical brakes. They're required by law, even if electromagnetic braking (regen) can be as effective.

See how this problem was overcome with this hub motor driven pickup: http://ecomodder.com/forum/showthrea...50-a-5914.html

(disc brakes on the drive shaft)

Another problem is that hub motors large/powerful enough for automotive applications are new, so expensive & relatively rare.

And here's a retrofit kit that doesn't replace the wheel with a hub motor, but adds one to the existing wheel:



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[Christ]

Those were developed when LA reported 15 "boots" missing, I'm sure. LOL.

I still lavish the thought of a 600HP EV strobing down the street and getting to highway speed before I've made it out of my driveway...

[Clev]

Originally Posted by MetroMPG

One challenge of using hub motors in cars is what to do with the mechanical brakes. They're required by law, even if electromagnetic braking (regen) can be as effective.

Hub motors also have to be strong enough to withstand road impacts, while not being too heavy. The "easy" way around this is to use inline motors and halfshafts.

[Christ]

I'm not really sure what people who say this are thinking... considering that forklift motors are solid mounted, and take some really hard hits due to people not really caring about the health of the forklift... especially when they push the accelerator into reverse while still driving at nearly full speed forward... you dont think the instant, high power change in polarity causes a few variances in "normal" operation?

This also tails onto the fact that all these guys with EV's are vibrating the hell out of them.. and every time they hit a bump, the weight of the motor/transmission combo is forced to move inside the boundaries of the mounts they are attached to, many of which are solid at least at one point. You think this doesn't equate to "taking a hit"?

Granted, the hit will temporarily break down the magnetic field of the motor, and might cause some runout on the bearings due to the weight of the armature... but nothing more than what happens every day anyway.

The real bane of MIW (Motor in Wheel) designs is the cost effectiveness... there aren't too many motor designs that make it cost effective to have one in each wheel, not to mention the practicality. The company that provides those kits had to make a bunch of excuses as to why it was good to have. One of those excuses was 160HP PER WHEEL.

It's not practical or cost effective, honestly.. what it really is, is cool.

But as far as saying that the motor can't withstand "road impacts", I believe you're surely mistaken here.

[Clev]

Originally Posted by Christ

I'm not really sure what people who say this are thinking... considering that forklift motors are solid mounted, and take some really hard hits due to people not really caring about the health of the forklift... especially when they push the accelerator into reverse while still driving at nearly full speed forward... you dont think the instant, high power change in polarity causes a few variances in "normal" operation?

This also tails onto the fact that all these guys with EV's are vibrating the hell out of them.. and every time they hit a bump, the weight of the motor/transmission combo is forced to move inside the boundaries of the mounts they are attached to, many of which are solid at least at one point. You think this doesn't equate to "taking a hit"?

Granted, the hit will temporarily break down the magnetic field of the motor, and might cause some runout on the bearings due to the weight of the armature... but nothing more than what happens every day anyway.

The real bane of MIW (Motor in Wheel) designs is the cost effectiveness... there aren't too many motor designs that make it cost effective to have one in each wheel, not to mention the practicality. The company that provides those kits had to make a bunch of excuses as to why it was good to have. One of those excuses was 160HP PER WHEEL.

It's not practical or cost effective, honestly.. what it really is, is cool.

But as far as saying that the motor can't withstand "road impacts", I believe you're surely mistaken here.

Forklift and EV motors weigh 60 to 125 pounds or more--of course they're going to handle more abuse. Wheel motors need to be lighter to reduce unsprung weight. Besides, EV motors mostly experience tortional stresses and shocks to the shaft. The impacts a wheel motor receive are equivalent to dropping it on its side, with only the tire between the asphalt and the motor. This means stronger bearings, casing and rotor assembly.

[blueflame]

Putting a gearbox and clutch between the electric motor and road wheels seems to make sense re: unsprung weight, hypermiling coasting, and the flexibility having different gears. More tooling though...

I think the future could be hub motors?

Siemans offer here: Siemens VDO visualises the electric wheel hub motor

[Christ]

Originally Posted by Clev

Forklift and EV motors weigh 60 to 125 pounds or more--of course they're going to handle more abuse.

That statement is exactly the sole reason that MasterLock is still around.

People perceive weight to be strength.

Think about it like this. If you wanted to make an MIW EV, you wouldn't have to use that 48V motor. You wouldn't have to use a single 30HP motor mounted to the transmission. The motor wouldn't weigh in at 60-100 lbs.

You would be using 2-4 motors.

Now, worst case scenario, the each motor is 24V, 15HP, and only weighs 30-50lbs... roughly the same weight as many cars' wheel and tire combo.

Divide the original motor between 4 wheels, and you've got 4 motors, each 7-8HP, each 15-20lbs, each 12V.

Even when you consider removing the engine and transmission, drive line (CV axles or drive shaft) etc, you still have removed more weight than you're adding on.

Lets say that you take a 1989 Honda CRX HF (lighest, smallest engine), remove the engine, transmission, both axles, and all eletronics associated with both.

The engine weighs in at least 230LBS,
Tranny is another ~100LBS,
Axles are close to 40LBS,
Remove engine wiring, fuel tank, pump, lines, filler nozzle, filter, charcoal can, associated equipment ~30LBS (rough estimate)
Remove complete exhaust ~30LBS (depending on cat/muffler, etc.)

In total, you've lost ~400LBS.. now you can add those 4 EV motors at 60LBS each, and still be ~150LBS lighter... add in the electronics to run them, and you're ~100LBS (I have no true idea, that was a guess.), Add the batteries, and now you're JUST starting to get overweight.

Replace those 60LB EV motors with 20LB EV motors, that run on 12V, and produce 10HP each, and you've got roughly the equivalent of a bone stock Geo Metro anyway, as far as HP. Acceleration will probably be faster, since you're not waiting for the engine to get into it's "torque range"... E-motors have a torque figure while idle (potential torque), and you're not experiencing ANY drivetrain losses.

Now, you could still attach those motors to the chassis of the car, and attach from the chassis to the hubs using CV axles, but you'd experience at least some drivetrain losses, have another breakable component in the mix, be adding another 80LBS of weight (All 4 corners). And adding almost no benefit, other than "less unsprung weight" which isn't helping you at all anyway.