# Formula Hybrid



## kishor5466 (May 15, 2012)

hey guys ,
for a car to accelerate and complete a distance of 200 under 6 to 8 seconds what type of motor can be used and tuned easily???


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## frodus (Apr 12, 2008)

200 what? feet? meters?


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## kishor5466 (May 15, 2012)

Is it possible to achieve 200 meters under 10 seconds with any electric motor ???(If your car weighs around > 300kg approximately according to calculations)


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## frodus (Apr 12, 2008)

Do the calculations. Calculate the torque and power needed to accelerate a 300kg vehicle 200meters. Then come back and ask me if there's a motor that has that torque and power.

I can tell you YES, there is a motor that can do it, but it only races at 1/4mile at a time and does so in just under 7 seconds and goes 200mph.

If you need something for a longer race, things get more complicated. Cooling the motor becomes a huge issue.


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## Yabert (Feb 7, 2010)

kishor5466 said:


> Is it possible to achieve 200 meters under 10 seconds with any electric motor ???(If your car weighs around > 300kg approximately according to calculations)


 
Yes... some electric Jr dragster on this site doing 1/8 miles under 10 seconds.
But under 6 sec will be a good challenge (imply a really good power to weigh ratio).


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## Tesseract (Sep 27, 2008)

kishor5466 said:


> Is it possible to achieve 200 meters under 10 seconds with any electric motor ???(If your car weighs around > 300kg approximately according to calculations)


I'm replying here because I received a PM from you in which you asked me to solve your design problems. I don't mind helping people out but I'm not here to do anyone's homework!

If you are an engineering student then you ought to be able to figure out how to answer the above questions. First you need to determine the rate of acceleration given a distance and time, which which then also give you a final velocity. Next you need to figure out the amount of power required for the given mass and calculated velocity and acceleration rate.

After you've done all that you can then come here and ask for motor and controller recommendations. I can tell you right now that what you want to do is fairly simple and could easily be accomplished with low-end golf cart components.


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## kishor5466 (May 15, 2012)

I have done the calculations before and the calculations are like this..........
m=400kg
t=8s
distance to be covered is 200m
since the initial velocity is 0 the acceleration will be 6.25m/s^2
hence final velocity will be 50m/s
so the output required will be 400*50*6.25=125kw 
which is so huge?? Am i wrong in calculations?? or is the parameters taken are wrong??
or is it not possible to get the required outputs???


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## Tesseract (Sep 27, 2008)

kishor5466 said:


> I have done the calculations before and the calculations are like this..........
> m=400kg
> t=8s
> distance to be covered is 200m


You said 300kg and 10 seconds to go 200m. That's quite a bit different from 400kg and 8 seconds... So which is it?

EDIT: 48kW for 300kg/10s/200m vs. 125kW for 400kg/8s/200m - that's the difference between only needing golf cart components or having to use mid-high level EV components.


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## kishor5466 (May 15, 2012)

Yeah ....... so my calculations are correct ........... so i need the one for 400/8/200


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## iti_uk (Oct 24, 2011)

kishor5466 said:


> I have done the calculations before and the calculations are like this..........
> m=400kg
> t=8s
> distance to be covered is 200m
> ...


300kg and 10s would give an answer of;
(a = 4m.s^-2)
(V = 40m/s)

48kW

Less than half of your last number.

Which target are you trying to hit?

edit: lol too slow


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## kishor5466 (May 15, 2012)

The one for 400Kg/8s/200m


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## frodus (Apr 12, 2008)

What is the budget for batteries (and what monetary unit you're using)?

You said 6k, but didn't give units (which you need to start doing, using numbers with units is something an engineer should know how to do).

The battery pack is what I'd focus on. The 125kw motor is something doable, it's the battery pack that is going to be the hard part.


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## kishor5466 (May 15, 2012)

i think i had mentioned it as 6000$ ...............


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## frodus (Apr 12, 2008)

US dollars though, right? I just want to make sure others knew, you mentioned that to me in PM's.


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## kishor5466 (May 15, 2012)

yep,
it is 6000 USD........ and don't you think that with a 72 V pack we will be able to get the required power and torque..................


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## Tesseract (Sep 27, 2008)

kishor5466 said:


> yep,
> it is 6000 USD........ and don't you think that with a 72 V pack we will be able to get the required power and torque..................


Let's see... You need 125kW of power - not including anything to make up for various inefficiencies - and you want to use a 72V pack... Sure, no problem, as long as the pack can deliver 1736A without sagging. 

Realistically speaking, you are going to need at least a 144V pack and a 1000A controller or a 288V pack and a 500-600A controller. 

And if you want the RPM to be between 2500 and 3000 when delivering 125kW you are going to need a massive amount of torque - some 400-500Nm. 

You can certainly get a motor and controller capable of dishing out 125kW for useful lengths of time, and for less than $6000US, but that won't leave you much for batteries. You may want to consider scaling back your performance goals and/or finding ways to reduce weight (though 400kg is already pretty light for a vehicle that will be driven on roads...).


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## major (Apr 4, 2008)

kishor5466 said:


> ....... and don't you think that with a 72 V pack we will be able to get the required power and torque..................


Hi kishor,

You really should start doing some of these calculations. That is an important part of engineering education. I've seen the figure of 125kW, so simple math says you'd need 1736 Amperes from a 72 Volt battery. Do you think that is realistic? If so, you had better read up on the subject.

Also, a 72V battery will sag and not deliver a full 72V under load. The 125kW used was a battery output and does not account for drivetrain loss. And the 125kW was an average power over the acceleration period, so in reality, peak power will be higher.

Good luck,

major


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## frodus (Apr 12, 2008)

Sure, you could get 125kw with a 72V pack, but your batteries need to be able to supply well over 1700Amps to hit that 125,000W mark.

It keeps sounding like we're doing this homework for you.


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## frodus (Apr 12, 2008)

Tesseract said:


> You can certainly get a motor and controller capable of dishing out 125kW for useful lengths of time, and for less than $6000US, but that won't leave you much for batteries. You may want to consider scaling back your performance goals and/or finding ways to reduce weight (though 400kg is already pretty light for a vehicle that will be driven on roads...).


The $6000USD is apparently for battery only.


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## kishor5466 (May 15, 2012)

Actually you got me wrong ......... The cap on the battery cost is 6000USD and there is no other cap on anything.................... And i got your point........... so can you suggest me on this??
if we are going for a LiFePO4 battery pack then what controller do you suggest???


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## frodus (Apr 12, 2008)

Controller and motor aren't the problem, the battery is. A 125KW battery won't come cheap and at 72V, it's got to have some really badass batteries in there to supply over 1700A (more because the batteries sag).


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## kishor5466 (May 15, 2012)

I'm really sorry if i'm making you feel that you're doing homework for me ............. But though i may be knowing the things , it will be taken as a verification when you also suggest the same thing and they will be pretty much practical as you've worked on these kinds of stuff................The calculations even a small kid can do but we shouldn't be facing the practical problems later ........... If we face later then that time i can't come and ask in the forum. so i'm clearing everything out including very small stupid thing.......


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## frodus (Apr 12, 2008)

What motors, controllers and batteries have you researched?


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## kishor5466 (May 15, 2012)

The motor will be Yasa 750 with curtis 1238 controller and a LiFePO4 pack


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## frodus (Apr 12, 2008)

The curtis controller is an Induction Motor controller with no support for BLDC motors. The Yasa 750 is a BLDC motor.

The 1238 series controllers are limited to 130VDC and 650A, but at 650A you'll have sag, so still, only expect about 80kw peak.

What lifepo4 pack? what batteries?


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## kishor5466 (May 15, 2012)

frodus said:


> The curtis controller is an Induction Motor controller with no support for BLDC motors. The Yasa 750 is a BLDC motor.
> 
> The 1238 series controllers are limited to 130VDC and 650A, but at 650A you'll have sag, so still, only expect about 80kw peak.
> 
> What lifepo4 pack? what batteries?


LiFePO4 is the short form of lithium Iron Phosphate battery pack......... It is a lithium polymer battery pack used in some of the EVs.......


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## frodus (Apr 12, 2008)

I know very well what lifepo4 means..... 

I'm asking about WHAT BRAND and MODEL of cells have you looked at. Not all are created equal. There's 100's of manufacturers of lifepo4.


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## kishor5466 (May 15, 2012)

frodus said:


> I know very well what lifepo4 means.....
> 
> I'm asking about WHAT BRAND and MODEL of cells have you looked at. Not all are created equal. There's 100's of manufacturers of lifepo4.


Okay Presmatic cells or pouch cells may be............... hey are pouch cells available for such a voltage requirement though they have higher energy density???


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## frodus (Apr 12, 2008)

You still haven't answered.

What brands of cells have you looked at? Who makes them?



I'm not doing the work for you, come on, try harder. You said you'd compare what we tell you, against what you have done. I'm asking, what have you done?


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## ruckus (Apr 15, 2009)

Ok, I am thinking he needs a place to start. Most people start here:

www.evalbum.com

You can see lots of examples and can search by battery brand, type, controller, etc. When you find cars that are similar in performance to what you want, take note of the components used, research their cost and capabilities.

Then you will know a little something.

There are many paths to what you seek. Do you merely want to meet the target? Or do you want to build something cool? You mention 72v pack. I think you must have forgot a zero and meant 720v, yes?

In America we call this humor..


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## kishor5466 (May 15, 2012)

ruckus said:


> Ok, I am thinking he needs a place to start. Most people start here:
> 
> www.evalbum.com
> 
> ...


Thanks a lot.........!!!!


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## kishor5466 (May 15, 2012)

*Planetary Gear System*

Hey,
Can anyone who have researched on how best the speed coupling or the torque coupling suits a parallel hybrid race car , tell me the details????


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## kishor5466 (May 15, 2012)

*IC Engine*

hey, 
is IC engine sensitive to speed or torque ?? (In terms of operating efficiency??)


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## kishor5466 (May 15, 2012)

*Power Adding*

hey,
can any one brief me about how the powers of engine and the motor add up in a hybrid car???


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## Ziggythewiz (May 16, 2010)

*Re: Power Adding*

It's pretty simple on paper:

ICE + small Electric motor + main Electric motor - some frictional losses = power out

They also have clutches in between everything so mechanically it's obscenely complex but can produce up to 6 different driving configurations.


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## kishor5466 (May 15, 2012)

*Re: Power Adding*



Ziggythewiz said:


> It's pretty simple on paper:
> 
> ICE + small Electric motor + main Electric motor - some frictional losses = power output


So what ever may be the speed , torque will match and the power output will be same ........ Hence in a race car does it really matter if we choose speed coupling or Torque coupling???

[/QUOTE]They also have clutches in between everything so mechanically it's obscenely complex but can produce up to 6 different driving configurations.[/QUOTE]

Okay here are you referring to planetary gear system?? If not with what kind of other system will we be able to get those many configurations???


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## Ziggythewiz (May 16, 2010)

*Re: Power Adding*

A planetary gear system mixes the inputs, a clutch turns them on or off. With each motor separately clutched you can create any combination you want to maximize power or efficiency. 

I don't know anything about speed or torque couplings.


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## Coulomb (Apr 22, 2009)

*Re: Power Adding*



Ziggythewiz said:


> It's pretty simple on paper:
> 
> ICE + small Electric motor + main Electric motor - some frictional losses = power out


Yes, but often you can't get the peak power of the ICE and motor at the same time, so the total peak power may not be the sum of the ICE and motor peak powers (before subtracting transmission losses).

For example, Prius NHW20: ICE 57 kW, motor 50 kW, combined 82 kW. The combined power is a long way short of the 105 kW you'd get by just adding the ICE and motor peak power. The limitations are part of the design, so there is no simple formula for figuring out the combined power, at least in general.

[ Edit: source: http://en.wikibooks.org/wiki/Toyota_Prius#Versions ]


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## Coulomb (Apr 22, 2009)

*Re: Power Adding*

Actually, the main limitation in the Prius is the DC/DC converter. When the battery assists the ICE to produce power, it goes through a 201 V to ~ 500 V converter, which has a 20-25 kW limit. If you take it as 25 kW, then 57 kW ICE + 25 kW battery power = 82 kW input to the "transmission".

[ Edit: some of the ICE power is routed through the two motors, so their power isn't wasted; one or other may be maxed out depending on the vehicle and ICE speed and power. However, this path isn't through the DC/DC "bottleneck", so the 25 kW limit doesn't apply to that. ]


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## kishor5466 (May 15, 2012)

hey guys,
if we are using a dc motor (say yasa 750) and we are having a controller which is compatible with the motor then will it be necessary to have choppers in between???(say battery voltage is 300V).......
or does the motor controller will itself do the work of chopping off the voltage and current???


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## major (Apr 4, 2008)

kishor5466 said:


> hey guys,
> if we are using a dc motor (say yasa 750) and we are having a controller which is compatible with the motor then will it be necessary to have choppers in between???(say battery voltage is 300V).......
> or does the motor controller will itself do the work of chopping off the voltage and current???


Hello kishor,

You have started another thread with the same title, http://www.diyelectriccar.com/forums/showthread.php?t=74029 What's the deal? And you are a student doing a university competition, correct? Do you not think you and your team should be using your faculty and own resources?

BTW, the motor you refer to is an AC motor. And chopping off voltage and current???? This does not sound like a well phrased engineering inquiry. I do realize there my be some language translation issue, but really?

I don't mind helping a guy out, but teaching fundamentals to university students is someone else's job 

Regards,

major

edit: You might try reading a controller manual.


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## Elithion (Oct 6, 2009)

kishor5466 said:


> if we are using a dc motor (say yasa 750) and we are having a controller which is compatible with the motor then will it be necessary to have choppers in between?


No. 



kishor5466 said:


> does the motor controller will itself do the work of chopping off the voltage and current?


Voltage, yes: the motor driver reduces the voltage.
Current, no, the other way around: the motor driver increases the current.

By the way, do you now that formula hybrid has its own forum?


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## kishor5466 (May 15, 2012)

*DC Electric Motor*

hey is there any DC motor that matches the following parameters??
100Kw 700N-m 10000rpm peak??


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## major (Apr 4, 2008)

*Re: DC Electric Motor*



kishor5466 said:


> hey is there any DC motor that matches the following parameters??
> 100Kw 700N-m 10000rpm peak??


Not likely.


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## EVEngineeer (Apr 11, 2012)

*Re: DC Electric Motor*

http://www.diyelectriccar.com/forums/showthread.php?t=2198

maybe while ur looking u could help out others by filling in this chart, with the info that u find.


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## kishor5466 (May 15, 2012)

*Re: DC Electric Motor*



EVEngineeer said:


> http://www.diyelectriccar.com/forums/showthread.php?t=2198.


i found this motor on this site (http://www.cloudelectric.com/category-s/385.htm) 
The ME1002 is a Series Wound DC motor
48-144V VDC, 200 amps Continuous, 550 amps Peak 2 Minutes
25 hp Cont, 70.7 hp Peak @ 96 Volts
32 hp Cont, 88.4 hp Peak @ 120 Volts
38.6 hp Cont, 106 hp Peak @ 144 Volts
Efficiencies of up to 92%


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## EVEngineeer (Apr 11, 2012)

*Re: DC Electric Motor*

if you can please fill in whatever you find into the chart.


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## somanywelps (Jan 25, 2012)

*Re: DC Electric Motor*

You're not hitting 10000RPM on a Brushed DC motor...

Wait, aren't you that guy who was arguing for free energy a month ago?


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## kishor5466 (May 15, 2012)

*Re: DC Electric Motor*



somanywelps said:


> You're not hitting 10000RPM on a Brushed DC motor...
> 
> Wait, aren't you that guy who was arguing for free energy a month ago?


Actually Yasa 750 motor does suits the requirements mentioned , but it's AC motor.... so i was wondering if anybody could help us with that ratings motor but DC .........
and actually i did post about that ME1002 because i thought it does not come under any of the ratings listed in that table


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## somanywelps (Jan 25, 2012)

*Re: DC Electric Motor*



kishor5466 said:


> Actually Yasa 750 motor does suits the requirements mentioned , but it's AC motor....


As I stated, you won't find a *BRUSHED DC* EV motor that can do 10,000RPM.

The highest I've seen is 6800RPM, and it's nowhere near those specs, at least not for a useful time period.

Edit: the Yasa-750 page says top speed of 2000rpm...


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## kishor5466 (May 15, 2012)

*Re: DC Electric Motor*



somanywelps said:


> As I stated, you won't find a *BRUSHED DC* EV motor that can do 10,000RPM.
> 
> The highest I've seen is 6800RPM,


okay but which is that motor hitting 6800 rpm??
And leaving the 10000rpm part is there any possibility that a motor which has the rest ratings be found???
may be brushed or brush less........


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## kishor5466 (May 15, 2012)

*Re: DC Electric Motor*



somanywelps said:


> the Yasa-750 page says top speed of 2000rpm...


hey do you have much details about that motor???
actually i saw video on you tube about that motor and there the guy says it can only be directed coupled to wheels??? is that true??? if we are not directly coupling it to wheels can't we use that motor??? if you know anything about that motor then help.......


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## Semper Vivus (Apr 13, 2011)

*Re: DC Electric Motor*

Hello,

the Kostov K9 220V does 6800rpm nominal. Somewhere here in the forum a guy from Kostov has said, it is possible to does 8000rpm peak maybe...so that was just a very unoffical guess.
Power and torque are a little bit lower than your requirements. But you could use two in parallel...one is only 45kg .
Then you will get about ~ 440Nm / 150-200kW peak I would guess.

Kind regards
Tom



kishor5466 said:


> okay but which is that motor hitting 6800 rpm??
> And leaving the 10000rpm part is there any possibility that a motor which has the rest ratings be found???
> may be brushed or brush less........


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## kishor5466 (May 15, 2012)

*Re: DC Electric Motor*



Semper Vivus said:


> Hello,
> 
> the Kostov K9 220V does 6800rpm nominal. Somewhere here in the forum a guy from Kostov has said, it is possible to does 8000rpm peak maybe...so that was just a very unoffical guess.
> Power and torque are a little bit lower than your requirements. But you could use two in parallel...one is only 45kg .
> ...


oh thanks that information was useful...... but if we are going for only one motor then do you think we will be able to get at least 250N-m of torque with one motor???


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## major (Apr 4, 2008)

*Re: DC Electric Motor*



kishor5466 said:


> oh thanks that information was useful...... but if we are going for only one motor then do you think we will be able to get at least 250N-m of torque with one motor???


Here is the performance curve from the web site: http://kostov-motors.com/files/productattachments/6ff70418861d3230f01fc0340802fb1f_S220E01.pdf See for yourself.



kishor5466 said:


> this really confuses me ,........
> the power that the motor can supply is it not the nominal voltage of the battery*motor current??? or as it is calculated above as battery voltage* controller current???
> if second one is the case then can't we use a high current rated controller with a low power rating (comparatively) to get high output power??


Yes, you are confused. Try to contain your confusion to a single thread.

The manufacturer's published performance curve is linked above. Kostov does a nice job with their motor curves. It shows how the motor will behave.


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## kishor5466 (May 15, 2012)

*Power rating of a motor*

hey guys correct me if i'm wrong.......
If we are having a 32kw motor and the motor controller used is rated for 500A peak and battery voltage is 300V then we will be able to use the combination and get 150kw of power???


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## kishor5466 (May 15, 2012)

*Re: DC Electric Motor*



major said:


> Here is the performance curve from the web site: http://kostov-motors.com/files/productattachments/6ff70418861d3230f01fc0340802fb1f_S220E01.pdf See for yourself.


ya thanks ......i checked that and found that it can give 99kw of power at 6100 rpm........ am i right???


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## major (Apr 4, 2008)

*Re: Power rating of a motor*



kishor5466 said:


> hey guys correct me if i'm wrong.......
> If we are having a 32kw motor and the motor controller used is rated for 500A peak and battery voltage is 300V then we will be able to use the combination and get 150kw of power???


Maybe. It depends on many things. 500A times 300V is 150kW but at the point where it is measured, the battery terminal. What useful power is developed on the motor shaft will be less. And if the 32kW rating on the motor is peak, then it will not tolerate such a high load. If the motor can tolerate such an overload, it would not be for long, or frequently.

What did your professor say when you asked him?


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## major (Apr 4, 2008)

*Re: DC Electric Motor*



kishor5466 said:


> ya thanks ......i checked that and found that it can give 99kw of power at 6100 rpm........ am i right???


No. You had better learn to read a graph. You could ask your instructor or do a search on this forum and find where I have explained how to read motor performance characteristic curves.


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## ruckus (Apr 15, 2009)

*Re: Power rating of a motor*



kishor5466 said:


> hey guys correct me if i'm wrong.......
> If we are having a 32kw motor and the motor controller used is rated for 500A peak and battery voltage is 300V then we will be able to use the combination and get 150kw of power???


Battery voltage is 300 at max charge voltage? Or with each cell at 3.2?

You have to include battery sag.

1. number of batts x 3.2 = fully charged voltage under load.
2. Figure 80% actually gets to the wheels.


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## kishor5466 (May 15, 2012)

*Re: DC Electric Motor*



major said:


> No. You had better learn to read a graph. You could ask your instructor or do a search on this forum and find where I have explained how to read motor performance characteristic curves.


this must be correct ,,,,,,,
"I" at 6000 is 500A....
according to the formula given for "U" and the value of current, the motor will provide 206kw of energy right???


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## kishor5466 (May 15, 2012)

*Re: Power rating of a motor*



major said:


> if the 32kW rating on the motor is peak, then it will not tolerate such a high load. If the motor can tolerate such an overload, it would not be for long, or frequently.


okay tell me if it can tolerate that much of overload for less than 8 seconds???
And in general what is the fraction of the overload a motor will be able to take if it's overloaded to that extent under 8 seconds( say for safety 10 seconds)??


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## major (Apr 4, 2008)

*Re: Power rating of a motor*



kishor5466 said:


> okay tell me if it can tolerate that much of overload for less than 8 seconds???
> And in general what is the fraction of the overload a motor will be able to take if it's overloaded to that extent under 8 seconds( say for safety 10 seconds)??


Inquire of the motor supplier or test it yourself. Rarely if ever is an 8 or 10 second duty rating published for a motor. Again, what does your professor tell you?


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## major (Apr 4, 2008)

*Re: DC Electric Motor*



kishor5466 said:


> this must be correct ,,,,,,,
> "I" at 6000 is 500A....


No.



kishor5466 said:


> according to the formula given for "U" and the value of current, the motor will provide 206kw of energy right???


No.



kishor5466 said:


> 206kw of energy right???


You had better read a text book or ask your professor to explain the difference between power and energy.


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## somanywelps (Jan 25, 2012)

*Re: DC Electric Motor*



kishor5466 said:


> this must be correct ,,,,,,,
> "I" at 6000 is 500A....
> according to the formula given for "U" and the value of current, the motor will provide 206kw of energy right???


Do you know how to read a graph?


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## PStechPaul (May 1, 2012)

*Re: Power rating of a motor*

For electrical equipment such as transformers, overloads are based on thermal considerations and duty cycles. There is also the question of maximum temperature of the hottest spot in the device and what the insulation is rated for. So here is an example of overload duty cycle ratings. These are based on current overload, which is generally proportional to torque in a motor:

Continuous 100% duty cycle
1.4x 50% duty cycle 30 minutes ON 30 minutes OFF
2x 25% duty cycle 10 minutes ON 30 minutes OFF
3x 10% duty cycle 1 minute ON 10 minutes OFF
5x 4% duty cycle 10 seconds ON 4 minutes OFF
10x 1% duty cycle 1 second ON 2 minutes OFF

The duty cycle is based on the square of the current overload factor, because heat is based on the square of current when resistive losses predominate. There are also other factors to consider, so the device manufacturer should supply such information. The maximum ON times are determined by reading internal temperature during enginering specification testing, or they may be set by mechanical stresses due to high current and magnetic effects. An induction motor is limited by its breakdown torque. A series wound DC motor is limited by saturation and brush/commutator capacity.


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## kishor5466 (May 15, 2012)

*Re: Power rating of a motor*



major said:


> Inquire of the motor supplier or test it yourself. Rarely if ever is an 8 or 10 second duty rating published for a motor. Again, what does your professor tell you?


Our professors don't help us in projects that's why i'm here to learn many things that apart from studies i can learn and also they are useful information for our project........


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## major (Apr 4, 2008)

*Re: Power rating of a motor*



kishor5466 said:


> Our professors don't help us in projects ......


Unfortunate. Perhaps this fact should be brought to the attention of the school's administration.

But there are the fundamentals which those professors should indeed be teaching you like:


major said:


> You had better read a text book or ask your professor to explain the difference between power and energy.





major said:


> Hello kishor,
> 
> ......... And you are a student doing a university competition, correct? Do you not think you and your team should be using your faculty and own resources?
> .........
> I don't mind helping a guy out, but teaching fundamentals to university students is someone else's job .........


I also notice that you have dropped the university association from your signature. Which school do you attend?

I like the SAE formula hybrid and other student competitions. I have been a member of SAE for many years in the Detroit section. I am also associated with a university and participate in organized student competition activities involving EVs. 

I think that it is inappropriate for you or any student to use a resource like this forum to the degree which you attempt in your quest to obtain a design for your project. You are certainly welcome to read what is published here and to make an occasional query when you have done the background research and can phrase an intelligent question.


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## kishor5466 (May 15, 2012)

*Engine and gear box separation*

hey guys,
we have planned to use a Ninja 250r engine for our car...... We know that it's in unit production hence it comes with a gear box in a single casing and sharing the coolant ........... but we want to separate that gear box and put a different gear box??? is it possible??? are there any companies which do that????


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## kishor5466 (May 15, 2012)

*selecting a motor for a drive*

hi guys can any body suggest a dc motor of least weight for the following specifications

peak torque = 170Nm
Max. RPM = 3600
power = 60HP


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## somanywelps (Jan 25, 2012)

*Re: selecting a motor for a drive*

What voltage/amperage? (Controller?)


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## kishor5466 (May 15, 2012)

*Re: selecting a motor for a drive*



somanywelps said:


> What voltage/amperage? (Controller?)


voltage range of 200 to 220 DC ......... and 500A .......and i think that the controller with the motor as a unit must be fine........


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## Woodsmith (Jun 5, 2008)

Kishor5466,

I have merged all your threads into one so that those who wish to respond to your questions can see the whole of your progress and all the variations of the questions you are asking as well as the history of responses you have already received.

Please observe reasonable forum etiquette and ask your related questions in this thread and not populate the forum with numerous threads asking the same, or similar, or related, questions.

Thank you,

Admin


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## PStechPaul (May 1, 2012)

Thanks! It made for a rather interesting read. It has been like someone trying to use an arsenal of weapons from a slingshot to a cannon in an attempt to hit a target which might range from a bird to a tank 

It would be helpful if the OP could draw up a complete specification sheet for just what it is that he wants to accomplish. If there are multiple targets then a separate document (or page) should be drawn up, perhaps in the form of an Excel spreadsheet, so changes can be made and easily analyzed.

Another tool that I think is essential is a simulator such as LTSpice. It allows the display of schematics and estimated performance including things like start-up transients that are often ignored in calculations.

There is a lot to learn about EVs, and I'm grateful for the honest and sometimes blunt opinions and statements of fact that have helped me with my understanding of the subject. I got a book probably 10 years ago about building your own electric car and I have researched various types of motors and controllers and batteries for many years.

I am very much a "hands on" guy and I have built various mechanical and electronic prototypes which have taught me a lot. Now I am starting small by building an electric tractor or utility vehicle using principles that can be scaled up to passenger cars and trucks. I suggest that the OP do something similar, and report actual results with an engineer's discipline of careful measurements and repeating questionable experiments. 

I am happy to help the OP if he meets me halfway and slows down to understand a particular concept before flitting off in another direction. And I welcome the opportunity to engage in technical discussions with those who have had, or plan to have, actual experience with larger EVs, and I hope I can contribute as much of my particular area of expertise as I am getting from the good people on this forum.


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