Motor comparison spreadsheet

Electric Motors and Controllers
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Miles
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Re: Motor comparison spreadsheet

Post by Miles » Thu Nov 09, 2017 4:43 pm

justin_le wrote:Just an idea here but since we've now added the ability to input a custom motor on the ebike simulator page ( see https://endless-sphere.com/forums/viewt ... 2#p1324922 ), you could in principle add a column to this spreadsheet that uses the string and math functions to produce a direct URL for viewing this as a custom motor in the online simulator. The only thing missing in your columns right now is the one for the inductance, but everything else is there.
Wow! What a great idea!

I've been pretty busy with work related stuff recently and hadn't even noticed that you'd opened up your simulator for custom input. Thank you Justin!

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justin_le
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Re: Motor comparison spreadsheet

Post by justin_le » Thu Nov 09, 2017 6:27 pm

Miles wrote: I've been pretty busy with work related stuff recently and hadn't even noticed that you'd opened up your simulator for custom input. Thank you Justin!
Hey Miles, well I am most keen to see your own motor design simulated with this tool so get to work and fill in the missing pole and inductance details!

Also, I should be able to contribute a number of additional motor model details to your spreadsheet list, as I'm in the process right now of trying to go through and consolidating the info from all my many scattered motor dyno tests and dissections over the years.
Big Dummy Frame (yes This One, thanks ES!) with prototype 26" Grin all-axle front hub, Phaserunner controller, and 52V 11Ah Cellman triangle pack
My website: http://www.ebikes.ca
Please contact via email, info@ebikes.ca, rather than PMs, which are disabled

toolman2
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Re: Motor comparison spreadsheet, add simulator link?

Post by toolman2 » Thu Nov 09, 2017 10:54 pm

justin_le wrote:Just an idea here but since we've now added the ability to input a custom motor on the ebike simulator page ( see https://endless-sphere.com/forums/viewt ... 2#p1324922 ), you could in principle add a column to this spreadsheet that uses the string and math functions to produce a direct URL for viewing this as a custom motor in the online simulator. The only thing missing in your columns right now is the one for the inductance, but everything else is there.

For instance, if we look at the Joby JM1S motor, we have

11 pole pairs
94 rpm/V
.015 ohms
0.107 Nm hyst trq
0.00007 Nm/rpm eddy trq, which is .0000073 Nm/Rad/sec

If I assume that the winding inductance is .05 mH, then this can be expressed in the custom URL string as motor=cust_94_0.015_0.05_11_0.107_0.000007_0
The order is just KV_Ohms_mH_PolePairs_Hyst_Eddie_TransmissionLoss Append it to the URL like this:
http://www.ebikes.ca/tools/simulator.ht ... 0.000007_0

Of course the default shows it directly coupled to a 26" wheel diameter, while a motor like this would be geared down, so it might make sense to have the string default an initial effective wheel size based on the KV. Here's a more realistic set of parameters for this motor on an ebike:
http://www.ebikes.ca/tools/simulator.ht ... A&cont=C35
Yep, sounds like a good plan Justin.
I should have the measured inductance of the JM1S motor somewhere, and have plenty of data from the longer JM1 shown. It would be very interesting to see if we can replicate (on your simulator) the goings on at the track with this motor when approaching both its torque and rpm limits at around 21kw in and geared tall, there's some on board video from a road circuit practice day with these settings that shows a glimpse of the CA to get a good feel for how this can play out in the real world.

There are also some other potential contenders (weighing 2 or 3 times more) that ive dabbled with lately, they are yet to match the joby for output but the d7500 motor (also pictured) is a cheap option and is pretty easy to control and mount. I have accurate data from most of these types of motors and have dynoed/torque tested them to find saturation etc, often using a similar method to your locked rotor hub motor tests.

So yes, it would be really interesting to see how some of these motors come up on the sim, and be able to mess with gearing etc and see it all graphed out. and
happy to provide the data.
motors.jpg
suitable motors?

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crossbreak
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Re: Motor comparison spreadsheet, add simulator link?

Post by crossbreak » Fri Nov 10, 2017 7:58 am

nice feature, thx justin!

Hubmonster by John in CR http://www.ebikes.ca/tools/simulator.ht ... A&cont=C35
10 pole pairs
18.3 rpm/V
.016 ohms
0.756 Nm hyst trq
0.00052 Nm/rpm eddy trq, which is .000054 Nm/Rad/sec
inductance is assumed to be .05 mH

CroMotor V3 /QS205 V3 measured by me http://www.ebikes.ca/tools/simulator.ht ... A&cont=C35
16 pole pairs
11.1 rpm/V
.0386 ohms
1.606 Nm hyst trq
0.00092 Nm/rpm eddy trq, which is .000096 Nm/Rad/sec
inductance is assumed to be .05 mH
justin_le wrote:you could in principle add a column to this spreadsheet that uses the string and math functions to produce a direct URL for viewing this as a custom motor in the online simulator
tried that in row L for the Hubmonster. works so far 8)
Attachments
Motor Data V4.34.xls
(216 KiB) Downloaded 24 times

Ddt
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Re: Motor comparison spreadsheet

Post by Ddt » Mon Nov 13, 2017 10:43 am

Hello
Toolman2 do you have data about the 7500w btw motor?
How we can have a joby motor?

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Re: Motor comparison spreadsheet

Post by toolman2 » Wed Nov 15, 2017 9:00 am

Ddt wrote:Hello
Toolman2 do you have data about the 7500w btw motor?
How we can have a joby motor?
Yes no probs, the d7500w:
Its 4 pole pairs
66.8KV (with a brushless rc controller)
0.0205 ohms
And used only 98W to do 2627rpm from 39.3v

inductance is pretty high at 87uH, and pole count is low so any controller could run it.
Theres an excess of iron in the flux path, so it's unlikely to saturate even at 400A but i from what i have measured i would expect about 6.5kw of total (and mostly ir) losses for this 60 ish NM output.
-so maby half that current torque level and 5 or 6000 rpm is something it could do reasonably well.

btw the outrunner in that photo can produce 60NM at around a quarter of that power consumption..

And the joby's are no longer available to the public im afraid, Joe Ben told me they were selling the old motors below cost and they are now real busy producing a batch of new updated motors (that are apparently better all round than the JM1 :!: ) in a joint venture with NASA.

Let me know if you or other folks need further info.

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speedmd
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Re: Motor comparison spreadsheet

Post by speedmd » Wed Nov 15, 2017 10:33 am

Hi Toolman2

Good to see your posts. Love your videos also. The d7500 looks very much like my gng 450w kit motor. What is the gap diameter?

Been reluctant to jump into the JM1 mainly due to the mount setup. New motors the same? I believe you added a outer (sprocket side) support bearing on yours. Is that a must do?

The outrunner in the photo looks nice also. Can you share some more details on it.

thanks

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Re: Motor comparison spreadsheet

Post by ltu » Wed Nov 15, 2017 11:51 am

the outrunner in the picture look like the frc 20080,he can custom made hallback array magnet.
do you have more information about new update joby motor?
the new generation of high efficency electric motor,used mostly in formula e,are the ac syncronous reluctance motor...

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Re: Motor comparison spreadsheet

Post by toolman2 » Thu Nov 16, 2017 9:33 am

Thanks speedmd, the d7500 is the same sort of design as those gng or bht type motors but its a fair bit bigger.
The airgap is 90mm and a 60mm long stator and those outer bolt holes you can see in the case are 160mm apart, also the case is pretty long because there is a separate and adjustable hall and magnet ring at the back end a little like i made for the Joby -the halls are under the pink epoxy mounted on a thin fiberglass sheet in that pic.

The separate magnets to trigger the halls is often needed as you approach saturation to avoid stray fields from the energized coils giving false signals. likewise adjustable halls are a good setup because ive never seen the halls accurately placed by a factory when checking them with a cro..

And yea you wouldn't really want to rely on the relatively distant rear case of the Joby to take chain loads from the nose, but its a pretty simple thing to have bearings inside the sprocket and mount that internal shaft to the frame.
The new design of the JM1 has the same case, so will bolt straight in to the race bike but its a different pole count and a new stator, the internet knows nothing of the new motor from what ive seen other than some media reports of the joint venture/VTOL project, so i prolly should keep it that way.

The big (154mm) outrunner is an interesting motor, it produces torque very efficiently and has 0.2mm lams. its not happened yet but i believe this motor (at nearly double the weight though :wink: ) is capable of making more power than the JM1.
Ill post up info on a rewound version of it shortly.

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speedmd
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Re: Motor comparison spreadsheet

Post by speedmd » Sat Nov 18, 2017 2:15 pm

The big (154mm) outrunner is an interesting motor, it produces torque very efficiently and has 0.2mm lams. its not happened yet but i believe this motor (at nearly double the weight though :wink: ) is capable of making more power than the JM1.
Ill post up info on a rewound version of it shortly.
:)
Thanks, look forward to the data. Double the weight is still reasonably light if it has the extra torque at low power consumption I would think. Looks very promising for a single speed mid drive.

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Re: Motor comparison spreadsheet

Post by speedmd » Sun Nov 19, 2017 3:19 pm

ltu wrote:
Wed Nov 15, 2017 11:51 am
the outrunner in the picture look like the frc 20080,he can custom made hallback array magnet.
Looks like possibly the 150 Image

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