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Would you pay 10000$ for a DIY kit to make your car Hybrid ?

  • YES

    Votes: 14 15.7%
  • NO

    Votes: 75 84.3%

In Wheel Motor ... affordable

195K views 383 replies 60 participants last post by  brian_ 
#1 ·
Hi,

I have a factory in Cairo Egypt and want to produce affordable brush-less permanent magnet in wheel electric motors.

Because of low labor cost, we could custom made adaptor sets for different cars of our customers.

We are in the planning stage and want contact with people in the US that are introduced in to EV suppliers world for brainstorming, help in developing and subsequent distribution of Wheel-Motors in the US.
 
#249 · (Edited)
Hey Ikcl, calm down, please.
My latest post about the price of my Wheel Motor was not in relation to this ridiculous Tennessee University WM. I just wanted to make an overview about what it would cost us to make a car hybrid. I want it to be cheap, but it has to perform well. I want also to drive around town at max 50 Km/h for 10 km or so, like a Prius can.
For example the batteries: Feeding the appetite of 2 wheelmotors, that are standing still, and accelerating away with reasonably swift acceleration of the vehicle. In my case a 2000 kg Jag, uses for a few seconds HUGE amps. We speak about the order of 1000 Amps by 100 Volt. If you think to get that out of a 1000$ pack, think again.
No battery charger ? Are you kidding ? Electricity from the grid is very cheap and using the car engine to generate electricity to charge the batteries is not a suggestion I expect on this forum.

PS Ikcl, Major is from the "barkers don't bite" department. He plays the grumpy commenter. No prob with a critical comment. Better than being ignored!
 
#250 ·
Hey Ikcl, calm down, please.
PS Ikcl, Major is from the "barkers don't bite" department. He plays the grumpy commenter. No prob with a critical comment. Better than being ignored!
ok. that's ok then. as long as you don't feel intimidated by him, and understand that he's just... being a grumpy commentator.
 
#254 ·
I'm not going to get into this "pitching match", but I think the more technical parts of the discussion have merit. The percent improvement mentioned seems reasonable if the electric motor takes over most of the propulsion at very low speeds, and if such driving is a major portion of the entire profile. The regenerative charging might be most effective only during braking and long downhill coasting. Otherwise it would be best to use the ICE and an alternator and run it, with the clutch disengaged, at its most efficient point of RPM and power to charge the batteries optimally. This required some intelligent operator control, but that could just be prompted by an electronic display. ;)

I think a system like this could be effective even using much smaller electric motors. They could be used only for very mild acceleration and hill climbing ability, so even 200 lb of thrust, or 100 lb-ft per wheel, would be adequate on up to a 5% grade. If it is to be used only up to, say, 20 MPH, then that's about 300 RPM and only 6HP peak. This would be within the capability of a 500 Wh battery pack per wheel, which might cost $400, and at 20C it should provide 6HP. With a total of 1000 Wh, it would provide about 3 miles of range without recharging. But that's enough to get you through most stop-and-go traffic jams and you can always rev up the ICE with a 6kW alternator to charge up your battery pack in 10 minutes. :cool:

I think a system like this might be built for less than $1000 per wheel, and sell profitably for maybe twice that. It's not going to save the world and it will only give you a big economy boost if you are always stuck in stop-and-go traffic. Or if you are a mail carrier or meter reader. And it will also give you a minimal backup system to carry you to a service station if your ICE breaks down. And it will give you additional traction on ice and snow. I might make/buy something like that! :D
 
#263 · (Edited)
In Wheel Motor ...conclusion: unaffordable !

Ok ...
So, even on a DIY EV forum, except one, nobody want to spend realistic money to make his car hybrid ...
The poll is a sad confirmation.

Not prepared to give simply up yet !
I will stop this thread probably and join or start an other non commercial one in this forum. If the WM approach has to many weaknesses, lets start again.
I want to make my car hybrid !

We need a solution that is:

Cheap
Retrofitable (without using a grinder :D)
Over the counter parts
Performing

Hey Seniors, is there already a thread in the sort of: "let's make a normal car hybrid" in this forum? (with adding parts only, letting the car intact as it is)
 
#264 ·
Re: In Wheel Motor ...conclusion: unaffordable !

Ok ...
So, even on a DIY EV forum, except one, nobody want to spend realistic money to make his car hybrid ...
It is simply not economically or even environmentally reasonable to spend $10,000 or more to get a few percent better fuel economy and a few other benefits. I can purchase a car like my Saturn SL1 for well under $2000 and get 35 MPG average and 45-50 MPG on the highway. Even at $5/gallon I'd spend about $1500 to drive 10,000 miles or $0.15/mile and even a 100% plug-in electric still costs about $0.04/mile just for the juice, but the batteries will cost $0.10/mile.

I'd be very interested in a bolt-on wheelmotor system for about $2500 that would mostly benefit stop/go driving and would provide 4WD and emergency alternate propulsion. Maybe you should start another thread under that more realistic premise and take a poll and start working out the technical details.
 
#267 ·
Hybrid

I like my Jaguar. I can't afford the newest Hybrid Lexus, Merc, BMW etc.
If I could drive 100 miles with my car electric for a conversion cost of about 6000 Euro and if it would be legaly allowed in Belgium, than I would go imediatly 100% electric. But Hybrid is the next best thing. If I could do 10 miles around town pure electric and for the rest Parallel Hybrid for about 4000 euro :): that would a be an excellent compromise. This is a subject for an EV forum, because the E-range will depend on the cash you can afford for the batteries. I will start a thread to brainstorm open about that. Not with the ambition to sell a set, just to have input and show my progression so that others can dream along.
 
#270 ·
I like the idea of the trailer hitch pusher attachment. But I think it would be best to have the wheels mounted on a lever and pushed under the vehicle in line with the existing rear wheels, which eliminates the steering problems and also the safety and visual aspects of what is essentially a trailer. :)

It could be used as an emergency device, stored in the trunk and just slipped into the hitch receiver when needed. It could be designed only as a low speed high torque device that could push the vehicle to a place of safety. Or it could be mounted on a hydraulic or electromechanical arm which would contact the road surface when the speed drops below, say, 20 MPH. For maximum traction, or as an option in case of a rear wheel blowout, it could be made strong enough to lift the entire rear of the car. It would then become essentially a tricycle, with associated handling issues, but the existing rear wheels would be only a few inches off the pavement and would act as "training wheels". :cool:

I'd be very interested in such a device. A conceptual prototype could be constructed for under $1000, and it would be easily adapted to any vehicle with a hitch receiver. I like it! :D
 
#271 ·
A... much more affordable solution !

PStechpaul, An evenly simple solution for all rear wheel driven cars, like mine, might be to simply ad a time belt to one of the rear cardan axles. In this way we can simply put any motor in the booth of the car. It also solves the problem of gearing and the expensive sealing rings of the motor (booth is clean and dry) and last but not least, we can replace the very expensive rear earth magnets of our motor, with very inexpensive Ferrite Magnets. Because we are no longer limited to the very tight space inside the wheel. I see some music in this !


Picture of Jaguar rear suspension courtesy of this website.
 
#272 ·
let's go inside !

A better solution, but slightly more complicated, is to ad an axle under the suspension in order to couple just before the rear diff. In this way we can put the car in neutral and drive 100% electric. Ooh they will love this in on this forum, he JRP3 ... :D

 
#273 ·
Re: let's go inside !

A better solution, but slightly more complicated, is to ad an axle under the suspension in order to couple just before the rear diff. In this way we can put the car in neutral and drive 100% electric. Ooh they will love this in on this forum, he JRP3 ... :D

Considering my advice now?
About the only approach I see having true potential is tapping into the driveshaft on rear wheel drive vehicles,...
Belt drives like that won't work, at least not for long. You'll need to gear couple or maybe an enclosed lubed steel chain.
 
#279 ·
on board Motor ... affordable

According to this website: http://motorcycleinfo.calsci.com/Horsepower.html, the torque at the rearwheel (where the belt connects to the gearbox) goes till 1000 NM. The chart is in foot-pound, that converts to NM by approximate 1.35 . It makes no noice and needs no lubrication or adjustment.


We can combine both solutions depending on price and availability.
This chain gear set cost 170 euro HERE



My friend the mechanic is on his yearly holiday. I wanted to jump immediately to him to discuss this new direction in our Hybrid-izing project, but it will have to wait a bit.
 
#280 · (Edited)
#281 · (Edited)
I've been thinking about these:
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=4652

They are 2kW but at 193k and 37V they are 7000 RPM which is more easily geared down. $52 each with discount. But it's an outrunner. I had an idea to use six of these mounted on the axle and use 12 tooth 20 pitch pinion gears on each shaft ($12 ea). Then use a gear rack on the inside of the brake drum which is probably about 12" diameter and would have 240 teeth, cost of about $35. A This would be a reduction drive of 20:1 so the wheel would turn at 350 RPM. So using this method a 12kW wheel motor could be constructed for about $419 in materials.

It would not be too difficult to have 24 tooth and 36 tooth pinion gears on the motors and rig up a system that would shift gears by moving the motors radially and axially. These gears would add 6*$21 or $126 to get the second speed of 700 RPM and then 6*$31 or $186 to get a third speed of 1150 RPM.

This would not be a 15 minute bolt-on accessory but could be fairly easily made to replace the brake plate on the rear axle and the brake drum could be machined with the ring gear.

For caliper disk brakes you could mount the motors with the shafts on the outside of the disk, and you could just cut gear teeth on the outer circumference of the rotor. A simple machine shop operation and you retain the use of the brakes. The caliper may limit the number of motors, but you might be able to get larger ones or make do with three or four and lower power.

Here is my design for a wheel motor that I could build for a tractor application. These are three 1/4 HP (1/2 HP peak) 12VDC motors that I have. I'm showing three 12 tooth 20 pitch gears and one 60 tooth gear that is also the hub for the wheel. I'm showing an 8" pneumatic tire and wheel assembly from Harbor Freight, which has four bolts about as shown. The motors are mounted front and back on swivel arms so the pinion gears can swing out of the way. This is only a 5:1 reduction and my motors are 5000 RPM, so this will spin too fast and not have enough torque for a tractor. But this is just a concept.

 
#282 · (Edited)
affordable

Hi PStechPaul, happy to see that you also consider using Hobbyking motors.
At 52$ for 2kW we are at 26$ per KW and the in-runner of 6KW kost only 75$ that is less than half at 12.5$/KW.
The excesive RPM of 1000RPM/V is a problem, but we connect before the diff. The Jaguar diff has a 2.8/1 reduction and a BMW 740 has a similar 3/1 reduction. So we need an extra 13/1 reduction in the trunk of the car. For this we need a 2 stage reduction of 2 X 3,6/1. That will make 2 chain gears with diameter of about 6 cm and 2 of 22 cm. but ...
It will look like this: (I made the gears proportional in dimension on the picture)

But ... the top wheel will have to spin at 40000 RPM and IF that is possible ... I will have a noisy siren in my trunk :(
This will happen at top speed of the system and that is about 120 km/h, question is if it will be more noisy than all the rest at that speed.
 
#285 · (Edited)
Thanks a lot GonZo !!!
I have to go, but can't stop reading!

The article speaks about this RC BLDC Turnigy CA120-70 of 17KW at "only" 10.000 RPM !
They discuss it on Endless-sphere.com (where the picture comes from).



Hobbyking price 450USD or 360 euro

In the pdf article of "The University Of Western Australia" they conclude with proposing a WheelMotor with this Turnigy BLDC motor with gears. Very nice study! But still some way to go to make it weather prove.
 
#287 · (Edited)
I've also been looking at these motors:
http://www.ebay.com/itm/380364297736



They have a 540kV version, 5500W, 80A, but that works out to 68V and 37,000 RPM. Still, not bad for $257 including controller and free shipping. I think there is a formula somewhere about gear and belt drive efficiency. For 100:1 reduction from a high speed motor to a wheel I would guess you might have only about 70% efficiency. :(

This might be a better choice. It's 9HP PM 84V 4900 RPM for a starting bid of $300 + $59 shipping. But too big for a wheel motor, actually.
http://www.ebay.com/itm/170888695722
or a 2HP motor for $30 + $20 shipping
http://www.ebay.com/itm/120961125555

I still think, maybe, a multiple motor approach might be better. What is really needed is is reliable data and a good source of motors.

I found another motor that might be useful. It's 6600W 80kV 52V 4160 RPM maximum for $265:
http://hobbyking.com/hobbyking/stor...oMax_80cc_Size_Brushless_Outrunner_Motor.html

But if you can find three phase motors pretty cheap, *NEW* 1.5 HP 3400 RPM 56C $58 + $25 shipping:
http://www.ebay.com/itm/160652715791






Three of these per wheel would be 9 HP total which I think is plenty for a hybrid. $255/wheel.
 
#289 ·
I been using a lot of RC Brush-less motors and controllers for quite long time, usually they are quite good quality motors and very efficient for the porpoise they are made, that is moving propellers or small RC cars.

The efficiency is achieved because they are made with very light and open housings for cooling, thin plates on the stator in order to minimize looses, and small ball-bearings in order to save weight.
But this type of motors will not stand continuous work as they will have to do on a car unless they are modified.

As well you have to know that the power rating of RC motors and controllers is not the same as industrial ratings, with this I mean that if an RC motors is rated to give 1000W means that is able to give up to 1000W for some seconds (about 10s usually) same for the controllers.
Usually when we install RC controllers if the motor is able to pull lets say 30A we instal one that is able to give up to 50A or more and usually modified with more heat-sink added to them.

The ball-bearings on RC motors are replaced every 20-30 hours of use.
 
#291 ·
we want it all


Thanks for sharing your experience. We can learn from the RC motors.
I am trying if I can not get one of the Chinese motor lamination factories to sell me a stator that they already make in big volumes for an other client, to serve as the base for a BLDC design. Now that we are no longer constrained to the limited space inside the Wheel, we can also use cheaper magnets that are more bulky for the same power ...
If we combine all we learned so far, we could come up with a cheap compact liquid cooled BLDC that delivers enough power and RPM.

If somebody could help us out with following dilemma:
We are able to model a BLDC inrunner (with an outside diameter of 400mm and a stack height of 400mm too) that can produce 100Kw, but ...
We seam to have to choose between torque and RPM.
But we want lets say 500NM at 1000 RPM and 100Kw at 3000 RPM :confused:
We are of course limited by the Battery Voltage. When the motor spins fast, it produces high back emf, that counters the battery voltage and prevents high current. So for high RPM we need mucho Volt !!! and that is expensive. But than ... the RC motors turn at 40.000 rpm with only 40 volt.
 
#290 ·
Very valuable information! I think the same can be said for some of the cheap wheel motors and scooter parts advertised on eBay and elsewhere. They are certainly not designed to the same standards as industrial AC motors or DC forklift motors and others that are really intended for continuous use under often adverse conditions. It's really not wise to skimp on the motor or try to use something that was designed for hobby use or intermittent duty. Most of the cost and weight of an EV is still the batteries.
 
#292 ·
affordable

Before the trial ended I could still do this modeling:

it is a 60KW motor:




If we make this motor liquid cooled and with the proper bearings etc, we can have a compact usable motor for our application. Will investigate lamination or ready to wire iron motor parts from this motor starting. It has ferrite magnets. Price is very important, because expensive efficient super BLDC's are available, but not affordable ;)
160 Volt battery and 600 amps. If we stay at 100 volt, we can not get sufficient RPM. I hear Major already thinking: 160 V and 600 amps is not 60KW. At max RPM the motor does not pull max amps, because of the controller settings and back emf. But we need the 600 amps to make at lower RPM the torque curve flat enough. Than with lower volt. The controller must limit the amps when needed, to spare the batteries.
 
#294 · (Edited)
I know that the idea to use Wheel Motors is very attractive for electric vehicles due its simplicity. And actually they work very well on bicycles because they are very efficient vehicles.

Normal street cars are everything except efficient (Too heavy and bad aerodynamics) so I do not think that Wheel motors are the best solution for a conversion. May be as commented here they will be enough for a hybrid conversion.

Anyway my opinion is that Wheel Motors will be on future electric car as soon as we have produce lighter and much more efficient cars, that will happen quite soon, energy and raw materials crisis is hitting all society levels already...

Technically talking I suggest for a DIY Wheel Motors to use industrial torque motors (quite big diameters and high poles count)
In order to give you some help I have been looking on some motors manufacturers and I think I have found some that will meet the needs of an electric vehicle.
This company provides them without housing so, if you have access to a good metal workshop will be not difficult to make the appropriate housing.
They are in-runners witch is very good because will simplify the cooling, actually I think if the motor is well matched to the duty (oversized) then only air cooling will be enough.
Link: http://www.alliedmotion.com/Products/Series.aspx?p=10&s=1

Looking into the list I think the model MF0410015B with around 30Kw peak power and 325Nm peak torque will do the job.

Although as I commented before I think that this motors will work really well on a light and aerodynamic car but not sure if they will perfrom really well on a normal street car.

Hope it helps.
 
#296 · (Edited)
This company provides them without housing so, if you have access to a good metal workshop will be not difficult to make the appropriate housing.
They are in-runners witch is very good because will simplify the cooling, actually I think if the motor is well matched to the duty (oversized) then only air cooling will be enough.
Link: http://www.alliedmotion.com/Products/Series.aspx?p=10&s=1

Looking into the list I think the model MF0410015B with around 30Kw peak power and 325Nm peak torque will do the job.

Although as I commented before I think that this motors will work really well on a light and aerodynamic car but not sure if they will perfrom really well on a normal street car.

Hope it helps.
Difficult to find out what the motor really does. (Motor 25, because no graph of 15) has only 109NM at 600 RPM at 150 Volt on the graph. But in the text they claim from 129 continuous to 529 demag torque (we don't want to demagnetize the motor, so this number must be avoided) Or do I misunderstand the graph ? That would be 6 to 10 Kw without gearing ? Not ok for my 1800 Kg Jaguar. Do you have the price ?


Like you say Gonzo, cars should be light, but as long as there is not a ban on GM Silverado's and ford F's I don't want to drive on the same road with a with a super light Loremo. It is on the government to impose a maximum weight for cars. But I don't see that for the near future.
 
#297 ·
I have been thinking torque motors for some time now, but I would not use them as a wheel motor but a direct drive motor. High pole count allows them to make significant torque at low RPMs needed for direct drive. Future vehicle technology used direct drive axial flux motors on their Evaro car in the Xprize. FVT built their motors themselves anyone with the right machine skills can make these motors. http://www.phasemotorparts.com i bet many of the motors we buy actually come from this companies parts. If anyone has a torque motor designed for 20-40 kw and 600-800 rpm we reverse engineer it, and build a copy of it with the parts from this company, and save time.
 
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