# Motor help???



## dwolsieffer (May 11, 2011)

Hey guys,

Im a student at Purdue University, for the past two years we have had an all electric vehicle Grandprix (AKA electric gokart race). We are limited to approx 18hp peak and 14kw peak power. We are also limit to the number of watt hours and such but we can only run under a 72V system. There are alot of other various rules but thats the important one =]

We have been using a marsE motor thats slower than balls. Im just curious if any of you know of any better motors. I have searched for weeks and the only one i have come across is the AC9 which is a great motor. However, we want faster. do any of you know of any racing motors that are under the 18hp/14kW power ratings?? just curious. 

FYI if you would like to know more about what i do google purdue EV grandprix! This is a great place to learn more and get involved. Any help you can give is great.(We also got to race at the Indianapolis motor speedway this year and were going to win next year i promise you that lol)


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## frodus (Apr 12, 2008)

if you want faster, you are probably going to be limited by your hp/kw limitations more than anything. 

Do you want faster top speed? or faster acceleration? What kind of course?

14kw is about 200A on a 72V system. Can your batteries even source that? What batteries are you using? how much do they sag under a 200A load? What is the total onboard energy you can have?

volts is RPM, amps is torque


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## dwolsieffer (May 11, 2011)

frodus said:


> if you want faster, you are probably going to be limited by your hp/kw limitations more than anything.
> 
> Do you want faster top speed? or faster acceleration? What kind of course?
> 
> ...


Speed(RPMs), its a road course, most karts go 35-40 mph there were 3 karts running the AC9 motor that we wanted this year but our funds were limited. we won some scholarship money with our design and got some more sponsors so now money is no issue. Our batteries are more than capable of any draw so dont worry about that.

I spoke with a gentlemen from ener1 and he said he knows of motor and controllers that are better and within our hp/kW limit! i just want to search but i cant find anything good. 

I need a motor that does 6000rpm or preferable more. We can get the money we just cant find the motors. So if you have unlimited funds but are only regulated by hp/kW what motor would you get? Keep in mind this is a race and balance is an issue so it preferably needs to be somewhat light.


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## Jay64 (May 11, 2011)

You might want to look into the AgniMotors. Smaller than the Mars, but is stronger. Jozzer is selling some refurbished ones in the classifieds on this site. They go for about $1500 brand new.


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## dwolsieffer (May 11, 2011)

Jay64 said:


> You might want to look into the AgniMotors. Smaller than the Mars, but is stronger. Jozzer is selling some refurbished ones in the classifieds on this site. They go for about $1500 brand new.



theyre too slow! 

Although i know how to, we cannot regulate power apparently "it is to hard to regulate the teams during the race and we could change our system to produce more". The max or peak HP of the motor may not exceed 18HP or 14kW EVER! much like the AC9 motor @48V (never exceeds this value). The AC9 motor is ideal because it has the capabilities of 6000RPM but we dont want just that, we want faster! After all it is racing!!!


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## dwolsieffer (May 11, 2011)

More specifically, we have a very efficient 48V system thanks to a sponsorship with Ener1. So if at all possibly we are looking for a high RPM 48V motor!


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## Bowser330 (Jun 15, 2008)

The little I know from electric motors is that voltage is relative to rpm...the higher the voltage, the higher the RPM...


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## dwolsieffer (May 11, 2011)

yes yes, i know the charts and graphs! i need no lesson in the field! 

ive seen 48V motors that have higher RPMs than 72V motors, its all about the quality of the motor really. i.e. the 48V AC9 has 6000RPM however a 72V Mars Etech only is capable of 4000ish!

now i know that controllers play a large role and that the way the motor pattern is wound also plays an enormous factor. I just need a website or motor names that are capable of higher than 6000RPMs that are less than 18hp/14kW within a 48V-72V system


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## frodus (Apr 12, 2008)

Chilll out dude, we're helping YOU, and for free. Have some patience, since you're the one that isn't doing your homework, you're asking us to.

That being said.....

The reason the 48V AC9 has that limit is because of voltage. It's not the motor, its the pack voltage and the controller. The AC09 is at 48V w/300A controller and 6000RPM, the AC 12 is at 72V w/300A controller and 7500RPM, the AC13 is at 48V w/550A controller and 6000RPM, and the AC15 is at 72V w/550A controller and 7500RPM. They are all the same motor. go here:
http://www.electricmotorsport.com/store/ems_ev_parts_motors_acinductionsystems.php

same motor, same weight, same dimensions. The difference in RPM is 6000 compared to 7500, because of voltage (and the controller they use). That will limit your RPM.

So actually, that motor is illegal, since it is actually a "43HP motor", being run with a controller that limits the output.....


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## Bowser330 (Jun 15, 2008)

frodus said:


> Chilll out dude, we're helping YOU, and for free. Have some patience, since you're the one that isn't doing your homework, you're asking us to.
> 
> That being said.....
> 
> ...


+1 What he said...


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## dwolsieffer (May 11, 2011)

sorry, i just re read it it sounds cranky! ive just been looking at graphs for a week or so and i already know alot of the stuff. ive been in EV classes for a couple of semesters.

i know that my voltage within my system effect the RPMs of my motor. Like i said right now we have very good batteries from Ener1 that we are doing research for before they put them on the market. they are a bit on the heavy side but they have a lot of power. do to our rules we must run the two 48V packs in par. as not to exceed 72V and we unlike anyone else can run the race without a battery swap which is why we would like to keep them. Do to that though our shitty mars motor goes even slower do to the drop in voltage.

SO WE NEED THE BEST MOTOR =]

Yes we can use the AC9 motor 48V with the 350A controller because when you do the calculations you cannot exceed 14kW peak power(18hp)! however due to a few teams running that everyone now wants one because they're very very fast! I know their are better motors out there but i just cannot find them. i have searched day and night on google and im tired of it lol!!

Basically im just wondering if anyone knows of a high performance racing motors that have high RPM capabilities that dont exceed these limits? the faster and more lightweight the better!! i will say that our kart as of now weighs in the neighborhood of 500lbs=race ready(driver, batteries, and all) and the max weight is 625! these karts are tanks but they are fast(just not fast enough)


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## dwolsieffer (May 11, 2011)

Okay so you are right that, that motor has 49hp.

however we cannot limit down the power through the controller! race set up has to include a motor and controller that are not capable of anything over the 18hp peak. so the motor with the 350A i think is the only motor controller combo expectable! 

basically they dont want it like that because otherwise you could mess with your controller after inspections and get more hp much like putting additive in you gas karts gas(ILLEGAL)! so when the inspect we have to prove the max capabilities of the kart with race set up to ensure a some what fair race. which is why we will pay more for a better motor bc everyone has about the same hp just not the same RPM/Torque for motors


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## dwolsieffer (May 11, 2011)

just an FYI i swear im not a prick im just tired of wasting my life away lol! 

I have finally met my goal of stumping google too! its a question that it simply cannot answer


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## Jay64 (May 11, 2011)

Doesn't the kv value of the motor specs basically indicate the difference in rpm for a given volt? Have you checked out some of the large outrunner motors? I think there is the colosus that is supposed to run 12kw or something like that with a 75kv. It's been a while since I studied the specs on motors, so I don't know how that compares to what you are already looking at, but just throwing out some suggestions for you to check out. I saw someone who built a kart with 3 of them and it was a screamer. 3 would probably be out of your rules, but one might work within your rules.


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## dwolsieffer (May 11, 2011)

Apparently somewhere in England there is a 9000RPM motor that runs off a 48V system and is legal. somehow i find that oddly ILLEGAL but ill get more info and let you guys know!!

in the mean time be on the search for a motor that is fast as hell but under 18hp

Thanks guys.


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## frodus (Apr 12, 2008)

That's better.....


so there are people using an AC09 out there? Wouldn't that be "Illegal" too? I mean, the motor itself is rated for much higher power, but the controller limits it. I'd spend time getting those motors yanked from the competition.

Call these guys http://www.goldenmotorusa.com/index.php?pg=bldc
and especially these guys:
http://www.perm-motor.de/index.php?id=synchron-motoren&L=1
(PMS150)

here are some to check into, they might not have what you need, but they might know where to go, as they've already looked.

http://www.enstroj.si/Electric-products/emrax-motors.html

and a chinese site with a bunch of BLDC motors
http://www.ananda.com.cn/anandaenglish/product_list.asp?id=331

or a slovenian company that does controllers, might have an idea of motors too
http://www.piktronik.com/index.php?option=com_content&view=frontpage&Itemid=80&lang=en

I'd honestly look at BLDC (brushless DC) more if I were you (they're called PMSM too, permanent magnet synchronous motors/machines). LOTS of power.

good luck


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## EVfun (Mar 14, 2010)

Power is power. If you are limited to 18 HP just change the gearing to get the speed you need. That is all a special motor that goes 9000 rpm while making 18 HP motor is doing. 18 HP is 18 ft-lb of torque at 5252 rpm, it is also 10.5 ft-lb of torque at 9000 rpm, it is also 31.5 ft-lb of torque at 3000 rpm. HP equals torque times rpm divided by 5252. It works out the same if you use kilowatts, 746 watts (0.746 kW) equals 1 horsepower. 



dwolsieffer said:


> Okay so you are right that, that motor has 49hp.
> 
> however we cannot limit down the power through the controller! race set up has to include a motor and controller that are not capable of anything over the 18hp peak. so the motor with the 350A i think is the only motor controller combo expectable!
> 
> basically they dont want it like that because otherwise you could mess with your controller after inspections and get more hp much like putting additive in you gas karts gas(ILLEGAL)! so when the inspect we have to prove the max capabilities of the kart with race set up to ensure a some what fair race. which is why we will pay more for a better motor bc everyone has about the same hp just not the same RPM/Torque for motors


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## Bowser330 (Jun 15, 2008)

EVfun said:


> Power is power. If you are limited to 18 HP just change the gearing to get the speed you need. That is all a special motor that goes 9000 rpm while making 18 HP motor is doing. 18 HP is 18 ft-lb of torque at 5252 rpm, it is also 10.5 ft-lb of torque at 9000 rpm, it is also 31.5 ft-lb of torque at 3000 rpm. HP equals torque times rpm divided by 5252. It works out the same if you use kilowatts, 746 watts (0.746 kW) equals 1 horsepower.


dwolsieffer do the rules allow gearing to be used?


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## GerhardRP (Nov 17, 2009)

Bowser330 said:


> dwolsieffer do the rules allow gearing to be used?


Here are the rules:
http://evgrandprix.org/docs/Kar_spec_21611.pdf

Have you dealt with this rule?
"Batteries should be commercially retailed and available to any competitor. Custom built, custom ordered, or specialized batteries are allowed only after written approval from the EMT."
Gerhard


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## DIYguy (Sep 18, 2008)

Perhaps, . . . you need to look again at this from the battery perspective. 

You said something like being limited to components "not capable" of more than 18 hp. When looking at electric motors, they have ratings based on time. I think you know that you can run higher currents for shorter times on most all motors. So, this "rule" or target is a bit dubious. I run a 10 hp lift truck motor in my Mazda pickup. I can generate over 200 hp with it.

Now, you said you have the "best batteries". . but a bit heavy? I assume you are running lead? If you really do have the funding as you say, maybe you should be looking at lithium to get the weight savings and have no sag for the whole race. Go buy Kokams. If sag is an issue, you haven't reached your potential wrt battery.

Finally, as for the motor . . the efficiencies are often thrown about and highly regarded, however I'm not sure that applications see as much difference between them when the system is complete. For the most torque, it's series wound DC. As mentioned above, gearing is an interesting point. Obviously AC will give you a flatter torque curve to a higher rpm which is likely better for your application.


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## Yabert (Feb 7, 2010)

> I run a 10 hp lift truck motor in my Mazda pickup. I can generate over 200 hp with it.


It's why this regulation is a crappy one:

*3.4.9 *
– MOTOR SPECIFICATIONS – Overview​ 
Motors should be rated by the manufacturer to handle the expected power load delivered to it. The peak rating of the motor should not exceed 14kW. There is no limit on motor RPM, but teams should be aware of the manufacturer’s specification for their motor.​ 
It's like if someone don't perfectly understand an important fact about electric motor!!!!


And with this bellow you can set a Soliton Jr to peak power of 14 Kw:

Controller must be appropriately matched to the motor in order to stay within the 14​kW limit.


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## frodus (Apr 12, 2008)

agreed. They need to have units that actually measure the current/voltage of the battery packs IMHO.


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## GerhardRP (Nov 17, 2009)

frodus said:


> agreed. They need to have units that actually measure the current/voltage of the battery packs IMHO.


 They actually have that.. Real time transmission of the instantaneous power.
Gerhard


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## frodus (Apr 12, 2008)

if they have that, then why limit the rated power of a motor?

Just limit the peak power they can use to 14kw


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## dwolsieffer (May 11, 2011)

EVfun said:


> Power is power. If you are limited to 18 HP just change the gearing to get the speed you need. That is all a special motor that goes 9000 rpm while making 18 HP motor is doing. 18 HP is 18 ft-lb of torque at 5252 rpm, it is also 10.5 ft-lb of torque at 9000 rpm, it is also 31.5 ft-lb of torque at 3000 rpm. HP equals torque times rpm divided by 5252. It works out the same if you use kilowatts, 746 watts (0.746 kW) equals 1 horsepower.



yea we tried that with our motor this year. on a road course like were running you have to find the perfect balance between torque and rps. We basically had a 1:1 ratio and we were fast but since theres a lot of turning our lap times were shitty because of the loss in torque needed for the turns! 

i wish it was that simple


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## frodus (Apr 12, 2008)

can you use a transmission? or a CVT?

with one gear, you sacrifice torque for top speed, and top speed for torque..... so maybe you need 2 gears.


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## dwolsieffer (May 11, 2011)

DIYguy said:


> Perhaps, . . . you need to look again at this from the battery perspective.
> 
> You said something like being limited to components "not capable" of more than 18 hp. When looking at electric motors, they have ratings based on time. I think you know that you can run higher currents for shorter times on most all motors. So, this "rule" or target is a bit dubious. I run a 10 hp lift truck motor in my Mazda pickup. I can generate over 200 hp with it.
> 
> ...



okay,
so i just asked a really simple question with 1 variable(hp)! whats so hard about it!!! all i need is a fast motor =[

To answers a lot of questions and fill ya in!

if you read the rules really carefully the rules suck lol! however this year was only the second year for it so they are still working on it!

the race is 100 labs(about 35 miles maybe)!

total energy available will be limited to 8640 Watt-Hours for the entire race, regardless of battery chemistry! Ener1 donated about a million dollars worth of batteries to Purdue university for extensive research and feedback. They are not available on the market however all teams were given the opportunity to run these batteries as long as they complied with all Ener1 rules( and their were alot of them). So technically they broke their own rules but no one could bitch because they were offered to all teams. Cannot tell you specifics as they are not on the market yet but they are not lead and they will be used for actual electric cars( we have a 2 module system and i think i heard the cars will have 6)! The batteries carry pretty close to the 8640 W-hrs that we need for the whole race they do weigh slightly more than the thunderskys but it doesnt matter, we dont have to stop to switch out batteries( they have 2 packs we have 1)

to dumb down myself and all else on here, think of power as instantaneous voltage X instantaneous current which is exactly what it is. so while everyone know who can make a 15hp electric motor put out 30 idc....we cant! we have to have pass these rules( as dumb as most are) and have all our ducks in a row for rule specs....motor, controller, system voltage....and we must also prove our systems capabilities (PEAK HP).

we dont want to make a 15hp run 18hp because some teams did that and their motor caught fire! you can only abuse a shitty motor past its limits so far. which is why we are looking into the AC9 motor and trying to find more like it(OR BETTER)!


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## dwolsieffer (May 11, 2011)

frodus said:


> if they have that, then why limit the rated power of a motor?
> 
> Just limit the peak power they can use to 14kw


we cant do this because their is no real way to measure peak power in the middle of the race. 

we can show that it is possible prior, but we can also add bypasses or other devices to exceed this and their would be no way to prove/disprove that we exceeded the peak power!!


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## frodus (Apr 12, 2008)

I gave an entire post full of links, have you called any of them? 

I'm guessing no.


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## dwolsieffer (May 11, 2011)

frodus said:


> That's better.....
> 
> 
> so there are people using an AC09 out there? Wouldn't that be "Illegal" too? I mean, the motor itself is rated for much higher power, but the controller limits it. I'd spend time getting those motors yanked from the competition.
> ...



the bldc motors are good and light but not enough RPMs
same with the perm motors, if were going to speed a 1000+ we dont just want an extra 500 RPMs 

ive contacted two of the other and they said they will get back to me!
the controller place is a dead end!!!

thank you for your help, hopefully those two companies can help me out!


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## dwolsieffer (May 11, 2011)

to answer the transmission question. 

using a transmission would be to much, just another mechanical part we will have to maintain. couple that with weight limit and balancing it sounds nice but ive looked into it! its a dead end for a go kart race


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## DIYguy (Sep 18, 2008)

dwolsieffer said:


> okay,
> so i just asked a really simple question with 1 variable(hp)! whats so hard about it!!! all i need is a fast motor =[


OK, so you're the expert as you have read for a whole week. I understand now. 

You must realize that the electric motor is most like a "transmission" in an ICE application. It only transmits the energy from the batteries and applied by the controller. If you take 5 different cars with exactly the same battery and controller potential and all have motors that will transmit that energy through a drivetrain then as someone suggested the rest is simply torque multiplication or reduction through gearing and of course as it relates to the torque curve of the specific motor. You can't simply change the motor in one of the 5 systems and have markedly different and more powerful car.


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## dwolsieffer (May 11, 2011)

DIYguy said:


> OK, so you're the expert as you have read for a whole week. I understand now.
> 
> You must realize that the electric motor is most like a "transmission" in an ICE application. It only transmits the energy from the batteries and applied by the controller. If you take 5 different cars with exactly the same battery and controller potential and all have motors that will transmit that energy through a drivetrain then as someone suggested the rest is simply torque multiplication or reduction through gearing and of course as it relates to the torque curve of the specific motor. You can't simply change the motor in one of the 5 systems and have markedly different and more powerful car.


False. and can be proven very simply through research that has already been done! if you take the same driver, batteries, controller, gear ratios, all the set up and only switch the motor you could loose anywhere from 1 to 4 seconds a lap. these are motors simply ranging from 3000 to 6000 rpms

1-4sec a lap X 100 laps = 100-400 seconds in the race and the average lap time is about 30 seconds! now thats over kill because we tested simply with just our kart on the track and no outside factors but the motor! 

think of it this way a motor that says its capable of doing 3000RPMs under no load can be gear to go faster. but so can the motor that does 6000

in our race their are basically 3 factors. driver( we have a good one) batteries(as of now they get the job done) and motors!

weather the motor we get is more eff., higher torque/speed, weight, how much of a beating it can take, how much voltage or current can it take! so you see the simple solution for now is to just get the most badass motor we can find and worry about the rest later because then anything they can do we can do better!!!

which is why i have asked you guys for help, i am enjoying these conversations though


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## DIYguy (Sep 18, 2008)

dwolsieffer said:


> False. and can be proven very simply through research that has already been done! if you take the same driver, batteries, controller, gear ratios, all the set up and only switch the motor you could loose anywhere from 1 to 4 seconds a lap. these are motors simply ranging from 3000 to 6000 rpms
> 
> 1-4sec a lap X 100 laps = 100-400 seconds in the race and the average lap time is about 30 seconds! now thats over kill because we tested simply with just our kart on the track and no outside factors but the motor!
> 
> ...


OK kewl. Have fun.


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## frodus (Apr 12, 2008)

> the bldc motors are good and light but not enough RPMs


do your research before you start generalizing. You're new to this, so assuming doesn't do you much good. BLDC motors can (and do) spin at much higher RPM's than ACIM and PMDC motors. They (And ACIM) have the same issue you do now with a PMDC.... Voltage. You want higher RPM, go up in voltage. I've seen BLDC go past 12krpm, but high voltage.




> same with the perm motors, if were going to speed a 1000+ we dont just want an extra 500 RPMs


 So don't do PMDC, most will limit around 5k, and the agni around 6k, look only at ACIM and BLDC (PMSM) motors.



> the controller place is a dead end!!!


 Why's that? I've called several controller manufacturers and they give me a list of compatible motors or companies. THEY don't have the motor, but they may know who does. And in this case, the controller needs to be matched to an output of 14kw (per rules), so you'll need to talk to some of them anyway.


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## dwolsieffer (May 11, 2011)

Also, im not the one with a senior member by my name! i know im not an expert. I have taken a few classes that build and get into schematics and greater details on new Electric vehicles systems and also hybrid vehicles!! hell i hope to get a job when i graduate next year!

im not a prick or a asshole either im just saying ive done the research and the motor is what i feel is best for my team! I was also told i am not aloud to build the motor bc theyre scared i could hurt myself or others....blow me lol

by research i do not mean reading google articles either =] just for clarification! 

Our kart is a true electrical system on wheels equipped with safety and legitimate materials. I have made my own ghetto kart much like the 70000 watts you see on youtube but that is not what this is about! 

i am just in search of a badass motor


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## dwolsieffer (May 11, 2011)

frodus said:


> do your research before you start generalizing. You're new to this, so assuming doesn't do you much good. BLDC motors can (and do) spin at much higher RPM's than ACIM and PMDC motors. They (And ACIM) have the same issue you do now with a PMDC.... Voltage. You want higher RPM, go up in voltage. I've seen BLDC go past 12krpm, but high voltage.
> 
> 
> So don't do PMDC, most will limit around 5k, and the agni around 6k, look only at ACIM and BLDC (PMSM) motors.
> ...


did not mean to step on your toes i swear! if you look at the graphs for those motors when they peak is normally with a 72V system and we cant run those motors with that bc then we exceed max HP. 

The perm motors are sick for the DIY street rod! however our rules suck and when you put our rules into effect with those motors they become( said to say this) average!

we basically need a low voltage, high RPM/torque motor, that is less than 18hp


this may sound like bull shit but we also wanted to run the Perm motor on our old 60V system and got denied. but the AC9 motor was run and now they cant take that away, i am simply looking for the next better version of the motor


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## dwolsieffer (May 11, 2011)

You're new to this said:


> unless your a true expert, meaning tesla or chevy pays your bills for ya with there EV programs or anyone else for that matter. we might be on the same mental capacity on this one. i lack the resources many of you have so i came to you. instead i feel like my question is just being attacked like im a rookie. I GO TO PURDUE UNIVERSITY I STUDY MECHANICAL ENGINEER TECHNOLOGY AND DO THIS SHIT EVERY DAY!!!!
> 
> quit talking to me like im a dumb ass and maybe then i wouldnt sound like such a dick. ive done the research for thundersky, im working with ENER1 to acheive the ideal kart, im working with professors that have ties to Ford, Chevy, Tesla for god sakes im not dumb.
> 
> I just came to you all because i know you enjoy it as much as i do and that we could put our resources togeather! but instead your just nit picking the little stuff


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## frodus (Apr 12, 2008)

dwolsieffer said:


> False. and can be proven very simply through research that has already been done! if you take the same driver, batteries, controller, gear ratios, all the set up and only switch the motor you could loose anywhere from 1 to 4 seconds a lap. these are motors simply ranging from 3000 to 6000 rpms
> 
> which is why i have asked you guys for help, i am enjoying these conversations though


But the issue is, you're coming off as kind of a jerk. I can see the patience running thin, not just with me.

You want help and you come on here expecting us to just have answers and just give you what you need. Yet, you're not really listening. You need to relax. This is your homework, not ours.

Realize, that we've been in this a LOT longer than you have. We know more. We've built more. We've helped WAY more people than just "you". Most of us with over 1000 posts HAVE that many posts because we spend our spare time, being a wet nurse for new guys like you.

So take that holier-than-thou attitude and save it for someone else. We're trying to help.

Regards,
Travis Gintz
BSEE Virginia Tech
Leviton Mfg., Inc.
Elithion, Inc.
Manzanita Micro


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## dwolsieffer (May 11, 2011)

hey man i understand this, ive been staring and looking at charts and going over the paper work just trying to get the best there is to get! i was working on this kart nonstop for the race not but a month ago while going to school! im just stressed

I understand where you guys are coming from and you are a huge help! i read this forum all the time, i just resently became a member because my resources have run dry and cannot find a motor. there are very smart people on hear i know

i am just looking for a great motor much like the AC9. if 10 teams out of 30 are using this same motor next year though then itd be kind of a boring race.

I just am trying to get my point across that i am not a newbee (even though i am to this site). 

So does anyone have a true high performance motor? please dont send me to electric motorsports or anything that has the same motors lol! i.e. motors like green motor sport's water cooled engine( although that motor exceeds the limits also)


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## frodus (Apr 12, 2008)

dwolsieffer said:


> unless your a true expert, meaning tesla or chevy pays your bills for ya with there EV programs or anyone else for that matter. we might be on the same mental capacity on this one. i lack the resources many of you have so i came to you. instead i feel like my question is just being attacked like im a rookie. I GO TO PURDUE UNIVERSITY I STUDY MECHANICAL ENGINEER TECHNOLOGY AND DO THIS SHIT EVERY DAY!!!!
> 
> quit talking to me like im a dumb ass and maybe then i wouldnt sound like such a dick. ive done the research for thundersky, im working with ENER1 to acheive the ideal kart, im working with professors that have ties to Ford, Chevy, Tesla for god sakes im not dumb.
> 
> I just came to you all because i know you enjoy it as much as i do and that we could put our resources togeather! but instead your just nit picking the little stuff


Since you had to go there......
I WENT TO VIRGINIA PolyTech, I STUDIED ELECTRICAL AND MECHANICAL ENGINEERING WITH A FOCUS IN POWER SYSTEMS, AUTOMATION AND CONTROLS AND DO THIS "SHIT" EVERY DAY. I WORK FOR LEVITON DOING LIGHTING CONTROL SYSTEMS, WORK FOR MANZANITA MICRO AS TECHNICAL SALES AND ELITHION AS TECH SUPPORT. I'VE WORKED IN POWER SYSTEMS AND CONTROLS FOR 10 YEARS NOW. I WORKED AT GE ON WIND POWER WHILE I WAS IN COLLEGE. I'VE WORKED IN AUTOMATION AND CONTROLS FOR MOST OF THAT 10 YEARS. FOR THE LAST 3 YEARS I'VE WORKED AS A CONSULTANT FOR: EVCOMPONENTS, MOTOVOLTA, BROOKLYN MOTORIZED, LIGHTNING RACING, ELITHION, MANZANITA MICRO AND A HANDFUL OF OTHER INDIVIDUALS ASKING FOR MY ADVICE.

I know you know Tony Coiro (buddy of mine) Do you know Brian Thompson? Robert Keller? David Rozovski? Morgan Hayden? I've worked with all of them over the last couple years...... Getting them set up with batteries, motors, controllers and other parts for their projects, ranging from motorcycles, to solar vehicles to karts.


So lighten up and watch your tone, we're helping. I will nitpick things apart to steer you the right direction. You're getting close to figuring out WHY you can't go high RPM and high torque. 


And BTW,
Congratulations on going to another Polysci school and having access to professors like I did. Pretty damn cool talking with engineers from GM and Chevy isn't it. I remember working with a couple of them on VT's hybrid back in.... about 2003 or so. Its a great opportunity and I wish they had more stuff like this when I was there. I'd go back if I could.


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## dwolsieffer (May 11, 2011)

lol there is no tone, its stress!

if you read all my post i think i apologize for about everyone time i get an attitude its just hard when i thought i was only asking for one thing!

For the record i am glad you do all that you have a very impressive resume! but i promise you im not just some dumb punk kid that thinks hes a no it all! remeber i came to you all for help! 

My team placed first in design at the INDIANAPOLIS MOTOR SPEEDWAY =] for the 2011 EV GrandPrix that just has my blood flowing for next year because sadly the motor we have is killing us and before we decide on investing i want to make sure its a damn good one!!


REFRESHING MY QUESTION!
so if you could have a motor/controller combo for these rules what would you choose and why! remeber 72V systems are fast but they also are heavier. dont forget your running a 100 lap race with a tight road course with 2 short straits!!!


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## frodus (Apr 12, 2008)

> lol there is no tone, its stress!


 one important thing is to seperate stress and work, because when you get an attitude with people and have a task to get done, no one wants to help and it makes things more difficult.



> if you read all my post i think i apologize for about everyone time i get an attitude its just hard when i thought i was only asking for one thing!


One variable changes others, right? That one limit of 14kw, means you limit 200A on a 72V system and ~300A on a 48V system. I assume you can reconfigure the cells for a 72V system right? You also have a give take relationship with RPM and Torque. Usually the higher RPM the motor, the lower torque it will have compared with a lower RPM one. It's basic motor design, and unless you have a multiwound motor, its a bit hard.

Have you considered a PMAC (BLDC) motor and doing a WYE/DELTA switch? Its a bit like a 2 speed, and gives you a bit of both worlds.




> For the record i am glad you do all that you have a very impressive resume! but i promise you im not just some dumb punk kid that thinks hes a no it all! remeber i came to you all for help!


never thought you were dumb, just a punk 



> My team placed first in design at the INDIANAPOLIS MOTOR SPEEDWAY =] for the 2011 EV GrandPrix that just has my blood flowing for next year because sadly the motor we have is killing us and before we decide on investing i want to make sure its a damn good one!!


 Congrats



> REFRESHING MY QUESTION!
> so if you could have a motor/controller combo for these rules what would you choose and why! remeber 72V systems are fast but they also are heavier. dont forget your running a 100 lap race with a tight road course with 2 short straits!!!


Well, its a really messed up set of rules because they don't know what they're really doing IMHO. We discussed this at depth a year ago with some people at purdue.

I mean, what is it, a HP limit on the motor, or on the system? The rules state its a motor HP limitation. But how can people use an AC9? Its illegal! they need to limit battery power to 14kw. Its too hard to put a limit on the motor, because you can just run it really hot and shove some insane power to it.

Can you use a mars double stack PMAC motor? and limit it with a Kelly controller?

what is the budget?

What are the volts and Ah of the batteries (I know they will work, just want to know more about em). Can they be reconfigured into 72V?


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## dwolsieffer (May 11, 2011)

unfortunately not. with the ener1 system its basically 2 48V batteries in 1 pack with 2 packs total on the kart! they are all run in par. we are also unaware of specs for the batteries besides that because they dont want word getting out to competitors but they do pack a mean punch.

i kinda just began reading on delt&star but have never seen one in person so not100 on how they actually work my understanding is basically a swith that when you dont need torque you can get speed???? is that correct?

lets just brainstorm and pretend there is no budget lol


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## frodus (Apr 12, 2008)

ok

I'm trying to nail down all of the Constants (can't change em due to rules or constraints)...... now we just gotta limit things down further.

So, system is 48VDC. How much do they sag under a 300A load?

delta/wye would have 3 phases on a BLDC motor. In one situation, you are running delta, like normal, the other would be wye. You switch in between to go into a high speed operation, with lower torque. Its hard to do the shifting via controller, but I think Kelly can do it, but the switch is manual.

look on endless-sphere a bit for Delta Wye


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## Tony Coiro (Mar 4, 2011)

Travis, thanks for bringing this to my attention. I left evGrandPrix several months ago for the reasons I think are becoming obvious. So many things that I want to say but I will start with the reason you, dwolsieffer, aren't getting the answer you want is because you're looking to violate conservation of energy. If you have a 14kW controller bottleneck, you can't make over 14kW motor side no matter how "badass" your motor is. However, the reason there was such a performance difference was real-time power use was not monitored. It was said to be an impossible task, although I bet anyone on here (even Frodus ) with a shunt, a couple resistors and a knowledge of microcontrollers could throw together in 20 minutes. Alltrax controllers were used almost exclusively, the 4834 and 7234. Both controllers have a 300A bottleneck but the 7234 has 50% more power due to higher voltage. This fact alone ruined the 48V ENER1 karts chances of winning (although not if a power monitoring circuit had been implemented.) Also, teams who battery swapped ran much lighter on the track and only lost under 35 seconds to pit stop. "To add speed, add lightness."


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## Jay64 (May 11, 2011)

I have a buddy that did WYE/DELTA on one of his motors, we had pretty much identical components, but when he got going and flipped that switch, it blew my motor away on speed.


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## dwolsieffer (May 11, 2011)

Tony Coiro said:


> Travis, thanks for bringing this to my attention. I left evGrandPrix several months ago for the reasons I think are becoming obvious. So many things that I want to say but I will start with the reason you, dwolsieffer, aren't getting the answer you want is because you're looking to violate conservation of energy. If you have a 14kW controller bottleneck, you can't make over 14kW motor side no matter how "badass" your motor is. However, the reason there was such a performance difference was real-time power use was not monitored. It was said to be an impossible task, although I bet anyone on here (even Frodus ) with a shunt, a couple resistors and a knowledge of microcontrollers could throw together in 20 minutes. Alltrax controllers were used almost exclusively, the 4834 and 7234. Both controllers have a 300A bottleneck but the 7234 has 50% more power due to higher voltage. This fact alone ruined the 48V ENER1 karts chances of winning (although not if a power monitoring circuit had been implemented.) Also, teams who battery swapped ran much lighter on the track and only lost under 35 seconds to pit stop. "To add speed, add lightness."


i understand 100% why you left because they all are going in opposite directions with the rules! we got denied for 2 motors and then saw them out running for race day.

I dont know if you know Ben from Ener1 but speaking with him are switching to a better controller! we also ran into the whole lower voltage same motor=slower kart no matter the ratio! 

i guess this has now turned into a question of how can the AC9 motor with a 48V system (curtus 300A controller) have such a higher speed output? is it the way the interior is wound?


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## frodus (Apr 12, 2008)

until they monitor peak power on the battery side (volts and amps) they're going to have problems. Limiting it on the output is a tall task to ask students to do.

The AC9 motor can spin at higher RPM than a brushed motor because the stator windings of this AC motor are wound that way. The 48V brushed motor just isn't wound the same, and as you go higher RPM, you reach mechanical limits of the brushes and the copper windings in the rotor. The ACIM doesn't have windings in the rotor, so it won't fly apart.

I'd stick with an AC9 and find other ways to reduce weight, increase efficiency, reduce rolling resistance, increase aerodynamics.

14kw is 48V 300A, just like the AC9, not much you can change about that unless you went higher voltage, which you can't. 

Maybe ask HPEVS to make you a race motor as light as possible.


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## dwolsieffer (May 11, 2011)

frodus said:


> until they monitor peak power on the battery side (volts and amps) they're going to have problems. Limiting it on the output is a tall task to ask students to do.
> 
> The AC9 motor can spin at higher RPM than a brushed motor because the stator windings of this AC motor are wound that way. The 48V brushed motor just isn't wound the same, and as you go higher RPM, you reach mechanical limits of the brushes and the copper windings in the rotor. The ACIM doesn't have windings in the rotor, so it won't fly apart.
> 
> ...



ive heard the different patterns do matter so do you think/know of any 48V 300A systems that are wound even better!I guess my question just sucked! thats what i mean by no means do i think im an expert but i do know alot more than your average joe....but i am humbled by tonys presence lol hes a GOD!

so again, not is there a more "powerful motor" (poor word choice i guess) but is there a motor that is better wound our has other factors that can contribute to higher RPMs?? we can go up in higher voltage to a 72V system but me and a buddy are going to do research for Ener1 possibly this summer so we'd like to keep a 48V system


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## Tony Coiro (Mar 4, 2011)

frodus said:


> until they monitor peak power on the battery side (volts and amps) they're going to have problems. Limiting it on the output is a tall task to ask students to do.


You'd be outta your mind to try to do it motorside, you would need an insane sampling rate to catch all the PWM. Battery side, all you would need is a shunt, some high precision resistors for a voltage divider circuit, microcontroller with two analog-ins and one digital out to flash a light if you drew over 14kW.


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## dwolsieffer (May 11, 2011)

Tony Coiro said:


> You'd be outta your mind to try to do it motorside, you would need an insane sampling rate to catch all the PWM. Battery side, all you would need is a shunt, some high precision resistors for a voltage divider circuit, microcontroller with two analog-ins and one digital out to flash a light if you drew over 14kW.


wouldnt the light still come on a little with voltage spikes? if you are running 48V and 300A your already sitting on the edge? what happens if your light flashes? do the DQ you lol


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## Tony Coiro (Mar 4, 2011)

dwolsieffer said:


> ive heard the different patterns do matter so do you think/know of any 48V 300A systems that are wound even better!I guess my question just sucked! thats what i mean by no means do i think im an expert but i do know alot more than your average joe....but i am humbled by tonys presence lol hes a GOD!
> 
> so again, not is there a more "powerful motor" (poor word choice i guess) but is there a motor that is better wound our has other factors that can contribute to higher RPMs?? we can go up in higher voltage to a 72V system but me and a buddy are going to do research for Ener1 possibly this summer so we'd like to keep a 48V system


Haha, and now I am the one humbled! The first thing you wanna look into is if you use 14kW controllers with no duty cycle, you don't wanna run 14kw peak motors. (Although the rules don't allow it, running larger sized motors would be safer. This is why I heard some Etek-RT's were sitting at 415 degrees F after getting off the track! ) Keep the motor cooler and the copper inside it will be less resistive (higher efficiency [and less fire]). Next, since the Etek's are perm-mag motors, back-EMF is really gonna limit power at high RPM (look up Lenz law for a background in this), you might wanna consider running a sepex for it's ability to field weaken. (And the bonus of easy reverse to get back on the track.) Since the majority of the race the karts are at 50% of top speed or greater, this might help quite a bit.


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## Tony Coiro (Mar 4, 2011)

dwolsieffer said:


> wouldnt the light still come on a little with voltage spikes? if you are running 48V and 300A your already sitting on the edge? what happens if your light flashes? do the DQ you lol


Controllers have large capacitors in them to act as voltage filters, this limits any spikes or transient effects. You want to filter out these spikes as much as possible battery side, huge spikes or irregularities in current is a great way to make your batteries unhappy. Motorside is a whole nother story, one that depends on the motor being driven but all modern controllers use pulse width modulation. Check out the voltage across the motor terminals sometime on an oscilloscope when you rev it up. This video is explains PWM well too: 





To monitor power motorside, you would need to count the length of each pulse very precisely, requiring a very, very fast sampling rate. Also, keep in mind that a 48V 300A controller is not always outputting 300A, amperage varies based on throttle position due to the PWM. The light would only go on if the amperage * voltage was over 14,000. If you wanted, you could even program in a double or triple check if you're really worried about transients or erroneous readings.


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## dwolsieffer (May 11, 2011)

Tony Coiro said:


> Haha, and now I am the one humbled! The first thing you wanna look into is if you use 14kW controllers with no duty cycle, you don't wanna run 14kw peak motors. (Although the rules don't allow it, running larger sized motors would be safer. This is why I heard some Etek-RT's were sitting at 415 degrees F after getting off the track! ) Keep the motor cooler and the copper inside it will be less resistive (higher efficiency [and less fire]). Next, since the Etek's are perm-mag motors, back-EMF is really gonna limit power at high RPM (look up Lenz law for a background in this), you might wanna consider running a sepex for it's ability to field weaken. (And the bonus of easy reverse to get back on the track.) Since the majority of the race the karts are at 50% of top speed or greater, this might help quite a bit.


we already tried to run a higher hp motor and regulating down to the 14kW but we got denied! i think this year i can convince them i was correct ( and they were wrong =]) because of the two cases of motors overheating! theyre so bad when it come to rules though that well see what happens! 

the sepex is so big and bulky! 

any advice on controllers? i give up on our alltrax it will make for a nice paper weight


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## dwolsieffer (May 11, 2011)

now that i think about it, we had the same motor as some 72V systems! if we were both "supposed" to have the same amout of output power how on earth were they that much faster during practice? 

i understand that RPMs are based off of voltage but we had more current=more torque! we geared the shit out of our kart and still couldnt catch up and started losing too much torque.....makes me wonder how many were using the wrong controller and actually exceeded the power ratings!!!


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## frodus (Apr 12, 2008)

higher voltage pulls the torque curve out further into the RPM range.


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## dwolsieffer (May 11, 2011)

frodus said:


> higher voltage pulls the torque curve out further into the RPM range.


makes sense, the delta wye im pretty sure is illegal! as far as i understand it basically is a transformer to step up the voltage which would exceed our power limits...does it work like a turbo??? pretty sweet stuff


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## frodus (Apr 12, 2008)

dwolsieffer said:


> makes sense, the delta wye im pretty sure is illegal! as far as i understand it basically is a transformer to step up the voltage which would exceed our power limits...does it work like a turbo??? pretty sweet stuff


Nope. It's putting the same windings in a different configuration. Look it up, delta wye switching. 

And even if you were right, and it was a transformer..... they don't increase power, they convert it from one voltage/current to another. Power stays the same. So its legal by their definition.


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## EVfun (Mar 14, 2010)

Hey Travis, I do have one thought on how to get better low end pull with a higher top speed, all while not increasing the power. I don't know how to explain it well and no idea what parts can be used that will fit the class rules, so I thought I would put it in on-road EV terms and hope that you or someone else could better figure out it might apply.

If you are using any one of a number of programmable controllers you can set the battery amps at 500 and the motor amps at 500 and have a power peak at a single rpm. You could also set the motor current limit at 1000 amps while the battery current limit is still 500 amps. This would create a large flat area of peak power by greatly increasing torque at lower rpm. Gearing could be taller without giving up low end acceleration. Alternately, this could be applied to a motor that will rev higher at peak power but needs the extra motor amps at low motor voltage to make the same torque. 

I don't know what motors and controllers could offer that kind of flattened power band for this application (especially since the rules seems confused, IMHO.)


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## Tony Coiro (Mar 4, 2011)

EVfun said:


> (especially since the rules seems confused, IMHO.)


You have no idea.......


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## DIYguy (Sep 18, 2008)

Tony Coiro said:


> If you have a 14kW controller bottleneck, you can't make over 14kW motor side no matter how "badass" your motor is.


Hmmmm, sounds familiar...


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## GerhardRP (Nov 17, 2009)

Tony Coiro said:


> However, the reason there was such a performance difference was real-time power use was not monitored. It was said to be an impossible task, although I bet anyone on here (even Frodus ) with a shunt, a couple resistors and a knowledge of microcontrollers could throw together in 20 minutes.


It seems that they have corrected this with transponder instrumentation.


*Rule 3.4.8 
*– POWER USAGE ENFORCEMENT – The power limits will be enforced by the race officials using power measurement equipment installed by the race officials before the race. Teams must make their carts and wiring schematics available to the race management team before 12/1 for installation of the measurement system. If a team is found to exceed the maximum power usage during the race, they may be removed from the event, or other penalties may be applied. The vehicle is subject to reinspection at anytime.
Gerhard​
​


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## dwolsieffer (May 11, 2011)

GerhardRP said:


> It seems that they have corrected this with transponder instrumentation.
> 
> 
> *Rule 3.4.8
> ...


not quite, some dont work lol! and we wired ours on the kart. so who is to say someone wouldnt cheat


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## piotrsko (Dec 9, 2007)

dwolsieffer said:


> not quite, some dont work lol! and we wired ours on the kart. so who is to say someone wouldnt cheat


my $.02:

expect cheating! cheat yourself, after all it is only cheating if you get caught. Don't ever get caught.

OTOH why not take a say 12/24v motor and use all the techniques and "over volt" it at 48 v to get extreme rpm? look see on the web about the golf cart racers or the "Power wheels" racing clubs. might need kevlar band reinforcement everywhere.


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## dwolsieffer (May 11, 2011)

piotrsko said:


> my $.02:
> 
> expect cheating! cheat yourself, after all it is only cheating if you get caught. Don't ever get caught.
> 
> OTOH why not take a say 12/24v motor and use all the techniques and "over volt" it at 48 v to get extreme rpm? look see on the web about the golf cart racers or the "Power wheels" racing clubs. might need kevlar band reinforcement everywhere.


dont want to cheat to win, not my style!!!
and im pretty sure if the 72V systems that had their motor over heat would agree that pushing the motor the whole race is not the right call! i could be wrong though...care to elaborate??


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## major (Apr 4, 2008)

GerhardRP said:


> It seems that they have corrected this with transponder instrumentation.
> 
> 
> *Rule 3.4.8 *
> ...


Hi Ger,

They never followed thru. No such system. Officials just looked at the carts and picked on ones they thought were too powerful or they otherwise didn't like. It was a pity they couldn't follow their own rules 

major


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## piotrsko (Dec 9, 2007)

dwolsieffer said:


> dont want to cheat to win, not my style!!!
> and im pretty sure if the 72V systems that had their motor over heat would agree that pushing the motor the whole race is not the right call! i could be wrong though...care to elaborate??


back in the day: Lotus's design theory was to ideally have just enough car to go across the finish line. If the car collapsed into a pile of debris upon hitting the pits, the design goals were accomplished. A lot of early Lotuses broke during those races. It was hard to get good drivers as a result.

There is a maxim today that states "if you didn't break something, you are not pushing it hard enough".

Yes it isn't elegant engineering to have a motor overheat, but calculated overheat may get enough performance to win.

If Major is correct ( he usually is) then a design goal would be to make cart look as underpowered or ugly as possible to pass tech inspection. This could be considered cheating by the purpose of intentionally fooling the inspectors.


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## Jay64 (May 11, 2011)

dwolsieffer said:


> dont want to cheat to win, not my style!!!
> and im pretty sure if the 72V systems that had their motor over heat would agree that pushing the motor the whole race is not the right call! i could be wrong though...care to elaborate??


That might be why other team's carts where so much faster. I'm a pro racer, and all the teams "cheat." But it's not always technically cheating. Basically you need to find the grey area of the rules. Sometimes you need to break the spirit of the rules without breaking the actual written rules. Sounds like the rules of this organization have a LOT of grey areas you can work around. I have found that usually it isn't until you get a huge performance advantage from a grey area of the rules that they change the rules for the following year to close the loophole.


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## alexcrouse (Mar 16, 2009)

MAYBE if i use a different font, you'll actually read this post:

_*MORE RPMs IS LESS TORQUE. A "FASTER" MOTOR IS JUST LIKE CHANGING YOUR GEARING. NO MATTER WHAT, YOUR HP LIMIT WON'T LET YOU BE FASTER!*_

Drop as much weight as you can, it's the only thing you can change to get more speed, without losing torque, without breaking the rules.

Hate to be a jerk, but you seem to not understand this, and act like WE are all idiots.


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## dwolsieffer (May 11, 2011)

has anyone come across any new motors that are less than 18hp?!?!?

jw lol we have gotten pretty far off topic =]


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## alexcrouse (Mar 16, 2009)

dwolsieffer said:


> has anyone come across any new motors that are less than 18hp?!?!?
> 
> jw lol we have gotten pretty far off topic =]


What you seem to be looking for is a more EFFICIENT 18 hp motor. That is the measurement of how much you get out of the same power in. Asking for a Faster motor will get you nothing, when you are limiting the horsepower.

Frankly, go AC, its the only way to get what you are looking for, and there are LOTS of kits in that power range!

http://www.thunderstruck-ev.com/index.php?dispatch=products.view&product_id=66


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## dwolsieffer (May 11, 2011)

alexcrouse said:


> What you seem to be looking for is a more EFFICIENT 18 hp motor. That is the measurement of how much you get out of the same power in. Asking for a Faster motor will get you nothing, when you are limiting the horsepower.
> 
> Frankly, go AC, its the only way to get what you are looking for, and there are LOTS of kits in that power range!
> 
> http://www.thunderstruck-ev.com/index.php?dispatch=products.view&product_id=66


how does eff. increase torque and RPMs by so much??

i was told that the way the motor is wound plays a large role in RPMs/torque also. that there are different patterns that create gains( or eff.)??


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## DIYguy (Sep 18, 2008)

What a number of people are trying to get you to understand is that, as I said before, the motor is best understood as a transmission. It transmit the power available at some level of efficiency and some type of torque profile. You will not generate more power out of the motor than what your batteries and controller deliver into it. You must select a motor that has a torque profile best suited to your application and with an efficiency as great as... well, lets say as great as you can afford. Additionally, the lightest motor possible and still able to not overheat from current. Beyond this may come other efficiencies including weight, rolling resistance, wind resistance etc. 
Now if there are "grey" areas in the rules (of which I have no idea), and you want to exploit higher power levels, again, it comes back to having the main components capable of doing this in the most efficient way.


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## frodus (Apr 12, 2008)

dwolsieffer said:


> how does eff. increase torque and RPMs by so much??


Would you rather the power you give to the motor terminals go to the motor shaft or into the air as heat? More efficient motors convert more electrical power to mechanical power than a less efficient one.



dwolsieffer said:


> i was told that the way the motor is wound plays a large role in RPMs/torque also. that there are different patterns that create gains( or eff.)??


Yes, but.....if it's wound for higher RPM, then torque suffers. If it's wound for higher torque, RPM suffers. They're inversely proportional (albeit not linear).


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## DIYguy (Sep 18, 2008)

I have a couple of Indramat (Bosch/Rexroth) brushless DC (AC) motors about this size at the shop. These are industrial motors, might be worth a look. I have no idea what the specs are at the moment. I could dig up a part number and take a couple pics next time I go, if u want. Maybe we could find a torque curve and other specs for them. Just a thought. Come to think of it, I have some AC servo motors from large robots also that might be big enough. hmmmmm.


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## dwolsieffer (May 11, 2011)

DIYguy said:


> I have a couple of Indramat (Bosch/Rexroth) brushless DC (AC) motors about this size at the shop. These are industrial motors, might be worth a look. I have no idea what the specs are at the moment. I could dig up a part number and take a couple pics next time I go, if u want. Maybe we could find a torque curve and other specs for them. Just a thought. Come to think of it, I have some AC servo motors from large robots also that might be big enough. hmmmmm.


very interesting =] lemme know what you find out!


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## DIYguy (Sep 18, 2008)

the indramat motor might be too much for your cart. I just looked up the sepcs. page 87 of this document. http://www.zmt.mt.put.poznan.pl/staff/WPtaszynski/Napedy/Silniki_MKD_27249507.pdf

The motor model number is MKD112B-058-KG1-AN. I think this thing may do a small car... lol. Somewhere in that doc is a description of model number. It has an encoder and brake.

it weighs 34kg. It's rated at 11.9 Nm torque and 4000rpm with "Natural" cooling. What is that...just over 12 hp? Although it can dish out 29 Nm with "Surface" cooling. Max theoretical torque is 102 Nm. This is where interpretation comes in as previously discussed. Use the "Rated" numbers and ur fine. It could likely take a lot more though. I dunno, check it out.


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