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Scott Drive 100kW AC motor & controller

174K views 441 replies 55 participants last post by  Hollie Maea 
#1 ·
efan said:
this controller+motor seem to be a new development, and I dont know of anyone who has used it..but it may be worth checking them out.

http://shop.greenstage.co.nz/product/100kw-scott-drive-ac-inverter-and-motor-package
Anybody actually seen or used this (new?) AC motor/controller combo? I see the Greenstage guys have a good history here, but this seems to be a first for them, and beats out the current HPEVS Curtis/AC50 combo by a good margin.

Thanks to efan for pointing this out!
 
#59 ·
Ruckus, can you explain to me the china new zealand link? Is it a chinese product with a reseller in new zealand, or is it designed in new zealand?

And please proof Tesseract wrong. Without bitching about it. Give us reliabale data. Especially a toque graph.
 
#67 ·
Please no more bickering in this thread, I like to see some competition, but I am looking for real solutions not a "whose **** is bigger" contest. You are both rational, intelligent adults, lets just leave it at that. I am very interested in this, and would like to purchase one right away for my own testing, trapezoidal or not. Tess. any chance you have some reading material for me on this subject? trapezoidal rotor" I would also like to know more about your motors as well, PM only please.

thanks for all of the input, some of it was quite useful,

Nintendo:cool:
 
#68 ·
Hello all,

Thanks for all the PM's. After talking with Phillip Court of Greenstage I think it is better to not release the unconfirmed torque graph. They are in the process of setting up the Scott Drive for full dyno testing and will have complete data in about 3 weeks time :). A line on paper seems rather weak relative to actual dyno results.

Also, if there are several early adopters (besides me), we could do a bulk buy and have a shipment of motors come direct from China rather than going through NZ. Obviously, the controllers would still come from NZ where they are made. By buying and shipping in bulk we could likely save a good bit on shipping and perhaps some on the goods as well.

All those interested say "aye".
 
#72 · (Edited)
Ok, crazy news here. :eek:

Greenstage ISN'T THE MANUFACTURER!! -just the NZ north-island dealer POSING as a manufacturer. They pretended to have sold the motor to Hagen (the guy with the RAV4) but actually he got the controller from his buddy SCOTT who is the builder. Hagen actually helped write the controller software, etc... It is no wonder Greenstage balked when I said I wanted to do a bulk buy at reduced price. They can't deal cause they are a middle man. Only the 'factory' can deal.

I am currently contacting 'Scott' to get the real scoop and will hopefully get more info about the system as well as a better bulk price for those willing to try something new.

Updates as story develops...
 
#73 · (Edited)
Hello,
Ok, since Greenstage is out of the game (as far as I am concerned), I might as well post the torque chart of the motor. Now please realize this is unconfirmed. It is also using the Chinese controller. If Scott will make a high voltage (540+vdc) version then the figures may be more, so this is just a rough image.



Might as well put the 320vdc version up as well: (I think it got a bit distorted going through powerpoint. :eek:)



Anyway, take them with a serious grain of salt. When the first shipment arrives in the U.S. I will initiate dyno tests to confirm.

Cheers :)

p.s. "norminal power" is a very specialized Chinese term combining 'nominal' and 'normal'. ~<:|
 
#82 · (Edited)
I was on the Kelly Controllers web site, and happened to see they have a BLDC system for sale. Note the graph looks very similar to the one below:

http://kellycontroller.com/mot/downloads/144V12KW_BLDC_Motor_Performance_Curve.pdf

http://kellycontroller.com/144v-12kw-bldc-motor-p-1072.html

http://kellycontroller.com/khb1440124-144v400aopto-bldc-controllerwith-regen-p-832.html

Here's a quick comparison:

Kelly ..... Scott

75 lbs ..... 176 lbs
80 nM ..... 500 Nm
$3100 ..... $6000?
3200 rpm ... 3200 rpm knee in curve

Anyway, note the same rpm for the knee. The Scott motor is about 2.3x the weight, but says it has 6x the torque and power. Keep in mind the Kelly system is much lower voltage and possibly lower current, so that could make for differences.
 
#76 ·
Here is a great gearing calculator. At the bottom of the page is a nice tire diameter calculator as well:
http://www.rocky-road.com/calculator.html

Direct drive 4000rpm with 3.54 gears and 28" tires (most common) gets you to 94 mph. :)

30" tires get you to 100 mph
Or overdrive gets you to 125 mph
Or higher R&P gets to about 130 mph

Combine the three and you get to 163 mph. :eek:

If you really need to go faster add larger tires or a separate overdrive...

Cheers :)
 
#78 · (Edited)
According to the motor manufacturer, 6000 rpm is the actual 'redline'. It will do 4000 rpm all day every day. I will be using a limit of 5000 rpm. Sounds like you have never driven a diesel. My old Cummins only does about 3k. :eek: -and it's towing to Missouri in September.

Ok, let's use a worse-case-scenario: a stock MR2 with teeny weeny 23" tires and super low 4.13 axle gears.

4000rpm is 80 mph.
5000rpm is 101 mph
26" tires get it to 114 mph
Drop in the popular 6-speed and you go 135 mph. (gas-powered MR2 only goes 120mph max)

If someone is going to completely change the drive system, swapping larger tires seems like child's play (if they really want to go over 100 mph).

The 110-120kw peak rating is based on pairing the motor with a small 150kva controller (not the Scott controller). The 320vdc motor is rated with about 400amps going through it. If 400 amps were applied to the 540vdc motor it should make over 160kw peak.

Obviously, this is pure speculation on paper and must be tested using a dyno while carefully measuring motor coolant temperature.

Remember, my Cummins only puts out 120kw and it pulls 20,000 lbs over steep mountain passes in 4th gear. It's all done with low-rpm torque.

500nm should allow you to 'merge' a heavy vehicle quite nicely.

Cheers :)
 
#79 ·
Yes but your cummins has a transmission.

Take for example, my van.

The original engine would output 334 FT LBS torque, and the transmission ( 1st gear) had a ratio of 3.06:1. The differential 3.73:1

So when you put the pedal down in 1st, you got over 3000 FTLBS torque at the wheels. They are 30 inch wheels/tires.


Of course, If you are putting the system in a car it should be quite alright though, assuming the figures are correct.

350 ftlbs at the driveshaft actually seems to move my van just fine, though I haven't tried to merge onto the highway.
 
#80 ·
The graph looks like 160 Nm (about 120 ftlbs)

Take one extreme, a 2000 lb car with a 4.1 rear end ratio, and 1 foot radius tires

( 120 ftlbs * 4.1 / 1 ) / 2000 lbs = 24% grade!

Now take another extreme, 1.5 foot radius tires, 3.23 rear end ratio, and 4000 lb car:

( 120 ftlbs * 3.23 / 1.5 ) / 4000 lbs = 6% grade (18% for a short burst)

The light car is fine, the heavy car not. It would be fine with a tranny, though. Note you could get up a much steeper short hill, this is for the 1 hour number long climb. The other caveat is this calculation is based on a spec sheet!

The RAV4 cited before I would roughly estimate:

( 120 ftlbs * 2.928 / 1.0 ) / 3600 lbs = 10%, but 30% for a short burst.

Yes but your cummins has a transmission.

Take for example, my van.

The original engine would output 334 FT LBS torque, and the transmission ( 1st gear) had a ratio of 3.06:1. The differential 3.73:1

So when you put the pedal down in 1st, you got over 3000 FTLBS torque at the wheels. They are 30 inch wheels/tires.


Of course, If you are putting the system in a car it should be quite alright though, assuming the figures are correct.

350 ftlbs at the driveshaft actually seems to move my van just fine, though I haven't tried to merge onto the highway.
 
#81 ·
400Nm = 295ftlbs from 0 to 2100rpm (118hp)
300Nm = 221ftlbs up to 3000rpm (126hp)
200Nm = 147ftlbs up to 4000rpm (112hp)

Seems like a good motor to mate to a transmission, as much power as the smaller European TDI engines with more low end torque not to mention torque form zero rpm; getting up to speed would be easier than waiting for a turbo to spool up.

The higher voltage version should push out the peak power rpm, right?
 
#86 · (Edited)
Here is a link to a short piece on National New Zealand news about Hagen's direct-drive Toyota powered by a windmill. That driveway does seem to prove that the motor produces ample low-end torque. Hagen has the controller limit set to 365 amps out of 590 amps potential. So he is only using about 60% of the available torque. He says petrol vehicles have a very difficult time getting started up the drive if they stop. They either stall out or rev up and spin the tires. The electric drive allows him very good traction control.

http://www.3news.co.nz/Kiwi-car-powered-by-windmill/tabid/309/articleID/257992/Default.aspx

Cheers :)
 
#88 ·
Thanks for the video link, that's neat.

  • It looks like the motor is in front to me, but it was kind of hard to see -- maybe he is actually using the tranny gearing?
  • He is the 3rd person I know of who has used "tow regen"
  • A falling torque curve does provide a form of traction control -- as the wheels spin faster it loses torque
Here is a link to a short piece on National New Zealand news about Hagen's direct-drive Toyota powered by a windmill. That driveway does seem to prove that the motor produces ample low-end torque. Hagen has the controller limit set to 365 amps out of 590 amps potential. So he is only using about 60% of the available torque. He says petrol vehicles have a very difficult time getting started up the drive if they stop. They either stall out or rev up and spin the tires. The electric drive allows him very good traction control.

http://www.3news.co.nz/Kiwi-car-powered-by-windmill/tabid/309/articleID/257992/Default.aspx

Cheers :)
 
#91 ·
Well, a couple of things... remember that grain of salt I was talking about?

20% is a very standard power loss factor used when roughly converting kva to kw. If you go to generator sizing calculations you will see it used often.

The controllers are measured in kva and the motors in kw. 20% is a very rough estimate of the TOTAL losses in the controller and motor at max power. (Let's not forget battery sag while we're at it). This is standard industry practice when sizing drive systems for a given duty and says nothing about the efficiency of these particular motors.

These are not dyno charts! They are merely pictoral representations of the motor specs already given in number form.
 
#103 ·
That paper was very interesting. :) My favorite part was:

"It is the author’s opinion that the difference between trap and sine [brushless motors] is surrounded by more misunderstanding and confusion than any other subject in the field of brushless motor control."

He claimed trapezoidal motors would have better torque than the other types. Of course, I don't think there is a good way to test that theory since any two motor designs could be flawed and not represent the optimized construction of their particular type, making comparisons quite limited in value.
 
#115 ·
Hey folks,
Finally have some rough prices. These are 'CFR' which means it includes freight, but not duty fees and import taxes which 'likely' amount to $1-300 based on the size and cost of the motor you purchase.

It seems that we will be able to group together with the folks in New Zealand for a bulk buy. This will get everybody a better price. The U.S.-bound motors will be directly shipped to the port of Seattle where I will pick them up. We can mix and match motor sizes and still get the bulk price. The ratings are in KW which you can multiply by 1.34 to get hp. The manufacturer says the peak power for very short duration (a 10-20 second drag race) is 4x the rated kw. The price somewhat depends on the size of the order. The first price column is for 5-10 motors and the 2nd column is for 10-15 motors.

Power 5+... 10+... $/kw Volts
22kw $1955 $1855 $84 3-400
30kw $2295 $2175 $73 3-400
35kw $2625 $2490 $71 3-400
40kw $2830 $2680 $69 3-400
45kw $2910 $2760 $61 3-400
55kw $3385 $3210 $58 3-400
60kw $4050 $3840 $64 5-600
Any motor size can be special ordered in higher voltage but will cost a bit more (10-15%).

The Scott controller will be priced about $3000 for the standard 400 amp version. The 600 amp version will likely be around $500 more which is not bad for 50% more power. The high voltage version doesn't have a price yet, but will likely be another couple hundred more.

It sounds like the order will be placed in the next couple of weeks. If you are interested, please pm me and we can work out the details of payment and shipping to your location. The prices above are rounded to the $5 for simplicity and include absolutely no increase from me. This is the estimated price off the boat but before customs and duties and taxes. These prices are subject to change by the manufacturer and shipper and may go up or down slightly.

Cheers :)
Do you have the torque curves (specifically for the 55kw motor).

Also I assume the RPM ratings are different.

Are these still BLDC?
 
#106 · (Edited)
The 22kw motor has a diameter of 250mm (9.85") and a length of 326mm (12.85").

The 30-60kw motors are all the same frame/casing and have a diameter of 300mm (11.81") and length of 403mm (15.87").

The Scott Drive pdf on the Greenstage link has a schematic with basic dimensions.

They get incrementally heavier as they go up in power since they have more copper and magnets stuffed inside.

I should mention that the motors normally come with an 8-spline shaft. We can have the shafts customized to our liking if we want. The folks in NZ have been making couplers/yokes for the splined shaft.
 
#112 · (Edited)
Ruckus, we need weight info.
I am putting together a table with all the info, but real quick here are the weights:

22kw 46kg 101 lb... 4.6 lbs/kw
30kw 63kg 139 lb... 4.6 lbs/kw
35kw 70kg 154 lb... 4.4 lbs/kw
40kw 75kg 165 lb... 4.1 lbs/kw
45kw 78kg 172 lb... 3.8 lbs/kw
55kw 85kg 187 lb... 3.4 lbs/kw
60kw 85kg 187 lb... 3.1 lbs/kw

For comparison, here are standard brushed motor ratings and weight:

8".. 16kw 107 lb... 6.7 lbs/kw
9".. 19kw 143 lb... 7.5 lbs/kw
11" 26kw 233 lb... 9.0 lbs/kw !

You can see the continuous power rating is much higher in the water-cooled brushless motors and their weight is much less.
 
#114 · (Edited)
Actually, the 8" and 9" values are for the ADC motors which are rated at 120v. Yes, it is too bad Warfield does not rate their motors at a useful voltage.

I listed the manufacturer's ratings. They are what they are. Your numbers are undocumented speculation.

Surely you know that the continuous kw rating of an electric motor is entirely based on its ability to get rid of heat. Raising the voltage does not improve cooling. The continuous kw rating remains almost the same. Peak power is higher, but not continuous power. This can be seen in the 55kw 320v motor and the 60kw 540v motor. The continuous kw ratings are hardly different. (40% increase in voltage = 17% increase in continuous kw rating which is 9% due to a higher rpm rating and thus only 8% actual increase in continuous power)

Sure, I could extrapolate the data of any motor to undocumented voltages/amperages and claim all sorts of crazy power using modified cooling systems, but that defeats the whole purpose of a manufacturer spec sheet, doesn't it?

Cheers :)

Edit: Since you don't believe anything I say, how about listening to Major? Here is his assesment (post #3):
http://www.diyelectriccar.com/forums/showthread.php/warp-11-hp-enough-motori-34418.html
 
#123 ·
...
I listed the manufacturer's ratings. They are what they are. Your numbers are undocumented speculation.
My numbers come from our dyno. I'd say that's rather more documented and rather less speculative than the manufacturer's. Besides, Kostov publishes perfectly good dyno charts that go well past 72V.

Surely you know that the continuous kw rating of an electric motor is entirely based on its ability to get rid of heat.
Surely you know that the vast majority of the heat produced by a series DC motor is the result of resistive losses (ie, I²R), but since power is the product of voltage and current, if you increase voltage without increasing current you get more power but not more heat.

...
Edit: Since you don't believe anything I say, how about listening to Major? Here is his assesment (post #3):
http://www.diyelectriccar.com/forums/showthread.php/warp-11-hp-enough-motori-34418.html
What's the problem? Major says that you can't get 43hp for 1 hour from a WarP-11 with a 72V battery... Run the motor at 120-150V instead of less than 72V and eve at its 1 hour current rating you'll get a lot more than 43hp out of it.
 
#132 ·
I'm going to stick my neck out with an opinion, based on my experience and theoretical considerations of 3 phase AC induction motors. I think they correlate fairly well, since both are magnetic machines and if you look at just the DC bus to the VF drive they look just about the same to the battery pack.

Under normal conditions, assuming the same number of poles and nominal voltage, torque, and speed values, speed is proportional to voltage, and torque is proportional to current. There are resistive losses with higher current, and core losses with higher voltage, and the limits are based on similar parameters such as heat build-up and insulation breakdown voltage and mechanical limits such as bearings and windage.

Both DC and AC motors may provide several times their rated power by increasing the speed while keeping current constant, which generally means also increasing voltage by the V/F ratio. At least for AC motors, but I think it is the same for DC. If you increase the load with the voltage constant, the current and torque will increase up to a certain limit. Induction motors generally stall at about 2-3x rated torque and are inherently current limited because they are inductors being fed by AC at a given frequency.

But DC motors produce much higher torque because their inductance can't limit a DC current. So they slow down, effectively lowering the applied frequency, and a stalled motor current is limited only by the resistance of windings and brushes. At the other end, increasing voltage and speed will keep current constant, so resistive losses will be about the same, but there will be more losses in the brushes, or possibly core losses due to the higher effective frequency.

Remember that (almost) all motors are actually AC. Traditional brushed DC motors use a commutator to provide the AC needed to cause rotation. I don't know the frequency or the number of poles in series wound DC traction motors, but I would guess that they operate at about the same frequency as induction motors for the same RPM.
 
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