Search found 30 matches

by toolbag
Mar 02 2017 6:49pm
Forum: Motor Technology
Topic: BLDC Magnet Grades?
Replies: 2
Views: 640

Re: BLDC Magnet Grades?

Typically 45SH is a good compromise with respect to field strength / temperature stability for hobby applications at high electrical frequency.

The price of 48H is similar, so in applications with better magnet cooling (or lower rotor losses) they can be a better choice.
by toolbag
Aug 19 2016 10:59am
Forum: Motor Technology
Topic: Anyone tried Hacker Q150 motor or Hacker HST-350 controller?
Replies: 21
Views: 6123

Re: Anyone tried Hacker Q150 motor or Hacker HST-350 control

I believe this is what E-Volo is using in the Volocopter. I've seen this pairing run on a dyno, and it's a little noisy which makes me think it's a quite simple six-step controller.

Looks like it uses hall sensors :roll: .
by toolbag
Apr 11 2016 12:44pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

FOC is just one way to determine the rotor position. Other sinusoidal controllers must measure/estimate rotor position in some way. The accuracy of this estimate will determine how well (and how efficiently) they work. FOC is not a method of rotor angle estimation; it is a method of directly contro...
by toolbag
Mar 27 2016 12:35pm
Forum: Electric Aircraft
Topic: Joby Aviation
Replies: 15
Views: 2940

Re: Joby Aviation

Check out one of Joby's other projects for an interesting read on propeller-propeller interactions having to do with acoustics: http://www.nytimes.com/2016/01/12/science/rethinking-the-airplane-for-climates-sake.html?_r=0 . The NASA guys are pretty convinced that more propellers allows for a multitu...
by toolbag
Mar 26 2016 7:54pm
Forum: Motor Technology
Topic: The limits of torque production for a given weight of motor
Replies: 107
Views: 10831

Re: The limits of torque production for a given weight of mo

The double rotor or double stator layout that Farfle mentioned gets you a little bit more torque per amp, and in an ideal world you can hope to see marginally more efficiency with one of those (on the order of 0.2% improvement on a 97% simulated efficiency). The trouble with those is that they suck ...
by toolbag
Mar 26 2016 12:28pm
Forum: Motor Technology
Topic: What motor would you choose for a 25kw paramotor setup
Replies: 51
Views: 8555

Re: What motor would you choose for a 25kw paramotor setup

The Zero drivetrain is awesome for reliability and the fact that it exists, but it is WAY too heavy (and high power) for this. A single FX drivetrain is big even for an ultralight.

Looking forward to seeing your results! This is a project I am keenly interested in as an aviation enthusiast.
by toolbag
Mar 26 2016 12:17pm
Forum: Motor Technology
Topic: High power VESCs for Robot Wars
Replies: 2
Views: 695

Re: High power VESCs for Robot Wars

I agree that the integrated gate drive unit is the weakest link on the VESCs. I've killed a couple when tuning the PIDs a little recklessly :roll:. To make for minimal software changes you could take the output of the VESCs gate drive through a buffer stage like Zombiess' here: https://endless-spher...
by toolbag
Mar 11 2016 7:45am
Forum: E-Vehicles General Discussion
Topic: GaN or SiC witch semiconductor MOSFET will be the best?
Replies: 4
Views: 710

Re: GaN or SiC witch semiconductor MOSFET will be the best?

Both GaN and SiC are improving so rapidly and decreasing in price so rapidly that it's hard to call either of them mature. They are both incredible even as the parts that you can buy right now, and they are only getting better.
by toolbag
Mar 11 2016 7:29am
Forum: Motor Technology
Topic: Game Changer Page 3 with video of 1700amps!!!!
Replies: 84
Views: 17836

Re: Game Changer

Have you looked at the loop inductance from that standoff layout? I started with something like that, but then I saw that the loop inductance from my loop (which was much smaller in area than what I'm seeing here) was an order of magnitude more than the ESL of the CAP :roll: .
by toolbag
Mar 07 2016 1:53pm
Forum: Motor Technology
Topic: Game Changer Page 3 with video of 1700amps!!!!
Replies: 84
Views: 17836

Re: Game Changer

Those SBE caps are indeed sweet. They even come with a 25mm thru hole if you want to get fancy putting one around an output shaft. One issue there is that you still need some bulk capacitance in addition to the awesome film cap. I'm using one if their 225uF 1200V parts on a very high frequency SiC i...
by toolbag
Oct 30 2015 3:07pm
Forum: Motor Technology
Topic: 5KW or more in a 10 inch scooter rim.
Replies: 6
Views: 1187

Re: 5KW or more in a 10 inch scooter rim.

So maybe someone can answer me this. Does a motor with two stators need two controllers to run? Or can the two stators be joined in paralle and be run by one controllerl? If the two stators are exactly aligned (very rigidly so), and the rotors are very well aligned (also very rigidly) then it could...
by toolbag
Aug 12 2015 7:10pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

Hmmm... The new firmware/bootloader makes the voltages read properly but has introduced a new issue where something errors out if I come off the throttle too quickly. Can we have the old '.ehx' file to run with for now (understanding that it has voltage calibration issues)? Edit: I've made too many ...
by toolbag
Aug 11 2015 11:46am
Forum: Motor Technology
Topic: My new 18 FET TO-247 layout riding video page 10
Replies: 308
Views: 46990

Re: My new 18 FET TO-247 layout riding video page 10

Setting the Amplitude control to 1200 and 60 seemed to make the current waveform more sinusoidal at low speed. The motor's inductance is about 12uH phase to phase; perhaps this is why we needed to set that parameter so high?
by toolbag
Aug 10 2015 10:20am
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

This controller seems to be really well matched to a 1500W leafbike motor. I'm running it on a tandem with a 1.8 kWh 12s pack. The sensorless operation is great. I'll probably get the halls hooked up so I can do 0 speed starts though. I haven't gotten my Cycle Analyst working yet, but other than tha...
by toolbag
Aug 07 2015 8:11pm
Forum: Motor Technology
Topic: My new 18 FET TO-247 layout riding video page 10
Replies: 308
Views: 46990

Re: My new 18 FET TO-247 layout riding video page 10

The facts are in: this controller rocks!
https://youtu.be/gSKvJtzarUc

Lookin' goooood :shock:
Image
by toolbag
Aug 07 2015 4:44pm
Forum: Motor Technology
Topic: My new 18 FET TO-247 layout riding video page 10
Replies: 308
Views: 46990

Re: My new 18 FET TO-247 layout riding video page 10

http://i1300.photobucket.com/albums/ag96/smacafee/Screenshot%202015-08-07%2014.25.16%20Lebowski%20wierd%20current%20crop_zps0yl33zcs.png Currently spinning zombiess' controller with a load and getting some strangeness on the current waveform. We're erroring out in various ways at a variety of power...
by toolbag
Aug 07 2015 10:17am
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

OK, I dialed the current regulator Ki way back and it seems to be stable now (was ~70, I set it to 10). Initial acceleration still seems a little sluggish so I tried boosting my motor current limit from my original setting of 60 A to the maximum of 74 A, but this caused similar faults so I left it ...
by toolbag
Aug 06 2015 11:58pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

Ran some more tests today and it's looking awesome! http://i1300.photobucket.com/albums/ag96/smacafee/Screenshot%202015-08-06%2018.32.32_zpsntnbhp3d.png (ignore the phase voltage readout, it's wrong) http://i1300.photobucket.com/albums/ag96/smacafee/Screenshot%202015-08-06%2018.35.48_zpshv1qmke0.png...
by toolbag
Aug 05 2015 9:30am
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

Got mine in yesterday and it looks great! My one concern is that it is displaying a different voltage on the DC bus in BacDoor than I see with a multimeter. Is there some sort of scaling factor I need to apply in BacDoor for this? I've been powering it with a mean well RSP-750 at 48V and the softwar...
by toolbag
Jul 30 2015 11:27am
Forum: Motor Technology
Topic: 3-phase + DC Motor/Controller test setup with LabView DAQ
Replies: 1
Views: 563

3-phase + DC Motor/Controller test setup with LabView DAQ

The 'Big Idea' with this DAQ is to get a better picture of what's really happening on the motor side of things when spinning with a load. I've instrumented the DC side on lots of systems, but now that I'm getting more interested in inverter design I thought it'd be good to be able to watch the phase...
by toolbag
Jul 28 2015 5:04pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

I ordered one of these as soon as they became available! I also ordered one of these thinking I'd use it to program the controller, but now I'm not so sure that's what that hardware does. Is the 'CA-USB' the right tool for working with the controller through BacDoor?
by toolbag
Jul 21 2015 8:01pm
Forum: Items for Sale - New
Topic: Compact Field Oriented Controller, ASI + Grin, limited run
Replies: 1271
Views: 279575

Re: Compact Field Oriented Controller, ASI + Grin, limited r

This controller looks totally awesome! I'm eagerly anticipating their availability :D .
by toolbag
Jul 21 2015 3:31pm
Forum: Motor Technology
Topic: My new 18 FET TO-247 layout riding video page 10
Replies: 308
Views: 46990

Re: My new 18 FET TO-247 layout riding video page 10

I have some high pole count inrunners that are on deck for load testing this and other controllers. They get up to ~1600 Hz when you're really pushing them, but normal operation is more like 1200 Hz. The two motors I usually use to test controllers are 20 and 22 poles, but there's a slower torquey 4...
by toolbag
Jul 20 2015 11:46am
Forum: Motor Technology
Topic: My new 18 FET TO-247 layout riding video page 10
Replies: 308
Views: 46990

Re: My new 18 FET TO-247 layout riding video page 10

I'm interested in the commutation frequency.