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Average Joe
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Discussion Starter #1
Was just thinking about this... I've heard certain cars have put a motor on each wheel, which seems like an engineering headache to me, but has anyone linked multiple motors up in tandem for a single very high-torque output? I would think that if you could rig it up reliably that pumped into a high gear ratio you could achieve some very high speeds as well as a solid low-end. Links? Info?
 

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Search the EVDL. Oh I kill me . .

Seriously, yes. I don't have links readily available, but there are a few cars on the austinev site. I think most people who do this use a Zilla controller with series-parallel current path switching.

I forget where I saw it, but I've also seen a parallel motor drive setup into a single transmission vs. the in-line arrangement I refer to above.
 

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Average Joe
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Discussion Starter #5
Yeah like that! Has anyone done more than 2? Maybe chain linked or something?
 

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If you check MetricMind's website (www.metricmind.com), they sell the Brusa ASM810 motor I mentioned before. This is a 3PAC motor, and it's made flat on each end. It's designed to be "stackable" with itself, so for more power, you can add additional motors. (And of course, a pile of money.) I think the armature shaft is at least partially hollow, so you can wind up with several motors all driving the same shaft.

The Brusa is just one example, but I'm sure any motor maker can come up with a configuration that allows motor stacking this way.

The problem I have with the idea of wheel-hub motors is the large amount of unsprung weight. If you're going to go with a motor per wheel in a normal passenger vehicle, it would be better to have the motors inboard, in the chassis, then have drive shafts and CV joints going to the wheel. This is for handling and ride quality.

-Mark
 

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That thought occurred to me as well Robert, but I have yet to see it done. It sounds to me like a viable solution to overcoming the lack of torque inherent with smaller motors if one wants to go with a direct drive setup through a gear reduction differential.
 

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Average Joe
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Discussion Starter #9
I guarantee you a belt would slip with high-power motors. You'd need a very heavy chain or even a geared setup. What I think would work well is a triangle of motors each with a small gear (maybe 15 teeth) attached to the output shaft, then a large gear in the center of the 3 with an output shaft in the center where the power of all 3 is transferred. I'd draw that up but don't have the time right now.

Side note - I forgot how the motors respond to series vs parallel wiring. I know it has something to do with the weakest one and balancing output but unbalanced draw.
 

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You have right idea for the belt, is not a great idea, gears are better.
If you connect the shaft of two motors. It is obvious they are connected in series. Like this the same current pass through the two motor and theirs torque are equal. If you connect in parallel, the difference between internal resistances generates waste. One motor wants to run faster than the other and the other brakes the first.



:)

I spend a little time to draw the twoo schematics for serie or parallel wiring of twoo DC motors.
I hope have time one day to explain the benefit of serie connection for connected safts.

Serie - parallel wirring of DCs motors.



;)
Her you are:
The math show that in serie n the speed of shaft is capable to be the same for the twoo shafts without wast.
In parallel mode n1 is not equal to n2 then it work not at the optimum.


Maths to present the adventage of serie wiring for connected shafts.
 

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I am interested in doing a four wheel drive jeep, I have a two wheel version now in full electric. Is this the forum that might be able to offer advice or can you suggest another place?

Eddie
 

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Thank you for your reply
I have a two wheel drive Jeep that I use for getting back and forth to work. It is a fully converted electric Jeep. I want to buy a four wheel drive Jeep so that I can participate in the Jeep Jamborees they hold here. I bought the 2WD Jeep in October of 2006, and drive it about 80 miles per day to work and back. I have never driven the Jeep until the batteries were dead but I was told that the maximum range on this battery was not less than 120 miles under normal driving conditions.
My motor control module is made by Curtis. The motor is a DC made by Advanced DC motors. The charger, battery control module, and the battery pack is made by LionEV. I put the web pages to each of those below.
First, I did not do the conversion on my Jeep. I bought it from LionEV in 2006. It was a track test vehicle down in Forest, Virginia. I can hold my own with mechanical work, and I am fair with electrical. I am comfortable with trying a conversion, it does not look that complicated.
My questions are
Can I just move the electric equipment over from the 2WD to the 4WD?
Do I need to add a second motor, or just buy a bigger main motor?
Should I figure on my driving range being cut in half?
The LionEV battery control module has a selector switch. It is set at 103.6VDC/400Ah. The other position is labeled 207.2 VDC/200Ah. Does this need to be changed if I add a motor. If I don't have to add a motor is there any risk or advantage to changing this setting?
http://www.curtisinstruments.com/
http://www.adcmotors.com/
http://www.LionEV.com/
I think that covers most of my questions. Thanks again for your reply.
Eddie
 

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Can I just move the electric equipment over from the 2WD to the 4WD?

Its possible.

Do I need to add a second motor, or just buy a bigger main motor?

I fink its better to use the same motor for test and use a bigger motor if you want much power. The 4WD Jeep is build for one motor. If you want twoo motor its need to connect motors in serie for road use and in paralelle for cross and wet use.

Should I figure on my driving range being cut in half?

You have to look the consuption of 2WD and 4WD. The twoo extra wheels use electricity, but no so much.

The LionEV battery control module has a selector switch. It is set at 103.6VDC/400Ah. The other position is labeled 207.2 VDC/200Ah. Does this need to be changed if I add a motor.

If you add a motor, its wired in serie with the first motor, it need a double voltage 207.2VDC, but on wet road, you risque that wheels slip and its important to use the paralelle wiring against that.

If I don't have to add a motor is there any risk or advantage to changing this setting?

Your motor is made for 103.6 VDC an extra voltage can damage the motor.
 

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Two conversions come to mind that use multiple PM motors (8+) as a drive source. Shawn Lawless' "Orange Juice" and Dave Cloud's racer, both of which worked well (although Clouds car was lost to a fire at the track earlierthis year). In general though you start adding up higher loses in eff due to friction and heat, ect when compared to using a single motor. With that said using as small a diameter a motor as possible (allowing quicker rotational rev up) can be an advantage for racing which is why you see twin smaller motors on racers such as White Zombie and Killacycle.

I'll have a little more input on this once Shawn Lawless get his new dragster "Juiced Up" running, which will use four modified ADC9" motors I built for him. Each motor will have it's own lithium batt pack and Zilla controller so it'll be as good a test as can be had on using multiple motors. In Shawn's case there really wasn't a valid "single" motor choice for a 374 volt 8000 amp drive motor, lol. If all goes as planned these will see at least 160 volts (to the motors) at 8000 amps (or what EVer 4 Zilla's will make) for some serious "hold on to your hat HP" and was IMO a better choice than using lets say Twin 13" motors. Anyway there really is more than one way to skin a cat and much depends on what it is you're looking to do, coupled with what is available, and or what's on hand for ones budget.
Cya

Jim Husted
Hi-Torque Electric
 

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Hey Robert

I see someone's given me an honorary title of sorts, you have anything to do with that, hehe? I found it very funny being I had seen my "newbie" title after signing up and thought, Man I got to get some posts out there and start climbing that ladder, so you must of had some kind of ear burning thing going on LMAO! Honestly not an issue as I'm not a status kind of guy but it was fun to see 8^)

Anyway, thanks for the invite here, I'm still getting used to the way stuff works as I'm new to the forum format but hope I can be as good a member here as I try to be at the EVDL and in general as a member of the EV community.

Cya
Jim
 

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Average Joe
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Discussion Starter #18
I saw your pictures and the title just popped into my head for some reason. You can change it if you want :)

I'm going to add some way to allow members to customize their title once they've hit senior member. I want to wait until they are senior so that the trust is established (avoiding vandalism, immature crap, etc..)

You're already established as a motor builder / vendor so I just put that in there for you.
 

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I am thinking of a dual motor set up for FWD minivan. Reasons for dual motors

1: switchable controller with 1/2 speed reverse
2: dual motors for increased power for heavier vehicle
3: independant motors to allow front steering with no bind

Question?
will one (example)500 amp controller actuate two 500 amp motors or will it burn up the controller. They will most likely be wired in paralell to accomodate free wheeling during a turn. If it will smoke, can the motors be series wired to the controller with nominal loss of power during cornering?

Will most likely set it up with each motor driving each front wheel independantly via C.V. axles through 6 to 1 reduction HEVY DUTY chain & gears.
 

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Alex, The way youv'e drawn your motors one will be rotating in the oposite direction to the other unless drive is off the auxilary shaft. Would silent chain be suitable for the reduction drive. I think that is what is used in some transfer cases.
 
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