Search found 786 matches

by major
May 26 2020 3:02pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

Two layers of five is better than single layer of ten turns needing longer core. Proximity of turn to steel core is insignificant magnetically, according to Ampere's Law. Folks have a hard time believing that.

Regards,
major
by major
May 20 2020 4:28pm
Forum: Electric Watercraft
Topic: minkota trolling motors
Replies: 5
Views: 269

Re: minkota trolling motors

In that case it depends on what is contained in the top part. What is its function? Got a link to a web page or manual?

major
by major
May 19 2020 10:01pm
Forum: Electric Watercraft
Topic: minkota trolling motors
Replies: 5
Views: 269

Re: minkota trolling motors

steve1981 wrote:
May 19 2020 8:55pm
I recently replaced a 55lb thrust 12 volt motor with a 70 lb thrust motor 24 volt. Can I now use two batteries to run the trolling motor or not? Will the top electrical handle it?
What does this mean? "Will the top electrical handle it?" Top electrical????

major
by major
May 19 2020 7:51pm
Forum: Motor Technology
Topic: electric wheels/hubs
Replies: 3
Views: 132

Re: electric wheels/hubs

Can anyone advise me to some contacts for electric wheels/hubs for vehicles/ light trucks This is the only serious attempt currently of which I am aware. And I doubt they will be successful. https://www.greencarreports.com/news/1128135_lordstown-electric-pickup-will-use-elaphe-in-wheel-motors-made-...
by major
May 16 2020 10:38pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: Quality of Kelly Controllers
Replies: 14
Views: 1076

Re: Quality of Kelly Controllers

Alexanderfoti wrote:
May 16 2020 3:58pm
Too high a current setting.....
IMO, a quality controller would protect itself from too high a current regardless of the settings.

major
by major
May 14 2020 11:16pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

:bigthumb: :bigthumb: https://endless-sphere.com/forums/download/file.php?id=273359 This is different than the C-core design. Here the two radial coil sides will pass thru the magnetic circuit carrying the charge (as current) perpendicular to the desired force (tangential), as well as being perpendi...
by major
May 12 2020 10:42pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

Hi APL, That second link is about SRM. You can view the diagrams without sign in. This one did have vectors. Has 15 C-cores/coils and rotor with 12 steel blocks on the periphery. From your post showing a 12 C-cores, I thought those were PMs. 2-Figure2-1.png An interesting oddity but not much good fo...
by major
May 12 2020 3:39pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

Thanks for the reply APL. But what I am interested in is how Lorentz force law is applied to this geometry. Namely the flux, current and force vector directions. Looks to me like the current and force ( or motion, tangential to rotor) are in common direction which doesn't work well with the required...
by major
May 11 2020 10:46pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

... also the fact that if one uses a 'C' core in a motor, the windings are no where near the core faces, and can't have anything to do with torque other than Lorentz transfer through the steel to the pole face. C cores.jpg ... Hi APL, Could you elaborate on Lorentz transfer for this geometry? Perha...
by major
Mar 31 2020 8:52pm
Forum: Motor Technology
Topic: FEMM Simulation Help
Replies: 4
Views: 138

Re: FEMM Simulation Help

If I'm reading the graphic right, you have essentially no magnetic flux encompassing current carrying conductors except for minor leakage. In other words, no interaction between flux and current.
Regards,
major
by major
Mar 28 2020 8:13am
Forum: E-Scooter and Motorcycle General Discussion
Topic: Quality of Kelly Controllers
Replies: 14
Views: 1076

Re: Quality of Kelly Controllers

I've never owned a Kelly, but have seen many. I was involved with TTXGP for a few seasons back 10 years ago. Maybe half the bikes ran Kelly's. There were bits and pieces of Kelly all over tracks in NA and EU. Looking at post mortem and attempted repairs in the paddock, Kelly internals sucked in desi...
by major
Mar 18 2020 12:49am
Forum: E-Bike Technical
Topic: Phase Amps vs Battery Amps
Replies: 18
Views: 783

Re: Phase Amps vs Battery Amps

Hi guys, This issue was discussed a short time ago. 3-phase power. Here's a short study I did a while back, for a different reason, but it shows some basic formulas. https://www.diyelectriccar.com/forums/showpost.php?p=376274&postcount=9 Regards, major That post is here: https://endless-sphere.com/f...
by major
Mar 02 2020 12:15pm
Forum: E-Bike Technical
Topic: MOTOR GURU'S, CHIME IN!!!: Which of these motors has better performance?
Replies: 11
Views: 723

Re: MOTOR GURU'S, CHIME IN!!!: Which of these motors has better performance?

In picture#1, it is obvious that the rotor which is shown is not the same as the rotor in the motor due to difference in the output shaft end. Also, on the opposite end of the rotor, at the edge of the photo frame, the commutator and wire connections are just visible. The motor may be BLDC, but the ...
by major
Feb 23 2020 11:23am
Forum: Motor Technology
Topic: 75 KW Axial Flux Motor Design Help
Replies: 15
Views: 1186

Re: 75 KW Axial Flux Motor Design Help

Hi ardillo, Very ambitious of you. Too much so, IMO. Suggestion is to start small, say, 0.75 kW. All design characteristic principles are the same. Just scale will save money in long run. Review APL's build thread if you haven't done so. https://endless-sphere.com/forums/viewtopic.php?f=30&t=97860 R...
by major
Jan 31 2020 12:12am
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

Not ready for prime time... 3D printing magnets. Just saw this today. https://phys-org.cdn.ampproject.org/v/s/phys.org/news/2020-01-sustainable-3d-printed-super-magnets.amp?amp_js_v=a2&_gsa=1&usqp=mq331AQCKAE%3D#referrer=https%3A%2F%2Fwww.google.com&_tf=From%20%251%24s&share=https%3A%2F%2Fp...
by major
Jan 29 2020 3:25pm
Forum: Motor Technology
Topic: Motor internal temp?
Replies: 5
Views: 391

Re: Motor internal temp?

Thermal inductance is just an analog to electrical inductance. Electrical inductance has no influence on thermal behavior of electric motors to my knowledge. Forget about it.

major
by major
Jan 29 2020 9:59am
Forum: Motor Technology
Topic: Motor internal temp?
Replies: 5
Views: 391

Re: Motor internal temp?

I think it was buried in the hub motor thread but looking for results comparing sensors within the windings revealing the wire’s true temp as apposed to just the case Hi, I suspect any general or "of thumb" rule will be inaccurate for your specific application. Of course, I don't know the tolerance...
by major
Jan 23 2020 4:28pm
Forum: Motor Technology
Topic: Revolt RV-series motor review and comparisons
Replies: 286
Views: 36079

Re: Revolt RV-series motor review and comparisons

... Peak efficiency is the point where while under load the copper losses and iron losses are equal. ... Hi John in CR, I've heard this statement a number of times recently. I don't recall having ever encountered it last century when I was learning motor theory. Do you have any idea of the source o...
by major
Jan 23 2020 8:40am
Forum: Motor Technology
Topic: Revolt RV-series motor review and comparisons
Replies: 286
Views: 36079

Re: Revolt RV-series motor review and comparisons

3-phase power.
Here's a short study I did a while back, for a different reason, but it shows some basic formulas.

https://www.diyelectriccar.com/forums/s ... ostcount=9

Regards,

major
by major
Jan 21 2020 7:06am
Forum: Motor Technology
Topic: Revolt RV-series motor review and comparisons
Replies: 286
Views: 36079

Re: Revolt RV-160-SH update

I have the RV-160-SH running on a 24 fet Nucular controller now. After a bit of set up, the motor is running great. At 82v I am seeing 6 battery amps and 10 phase amps under no load. It's not the best for efficiency as that's 820 watts just to run the motor. I'm sure with 3X the original copper cro...
by major
Nov 29 2019 10:51am
Forum: Motor Technology
Topic: OSU electric motor
Replies: 2
Views: 624

Re: OSU electric motor

Thanks for the heads up Jones. Interesting. The stator coils appear to be well over half conductor length as end-turn. But then again, that portion is of larger cross sectional area so mitigating resistive loss. I wonder how they fabricate the inside out cage on the rotor. Be awfully large for a die...
by major
Nov 19 2019 8:26pm
Forum: Motor Technology
Topic: aluminum windings
Replies: 3
Views: 851

Re: aluminum windings

Warren wrote:
Nov 19 2019 4:51pm
To show this in a direct comparison, the Fraunhofer team used 250W commercial pedelec motors.

https://www.greencarcongress.com/2019/1 ... -ifam.html
My BS detector is ringing off the hook. Any data or white paper showing verification testing method?

major
by major
Nov 07 2019 2:46pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

Hi APL, I'll refer you to a thread on end-turns mentioned before. This post in particular. There could be iron inside the solenoid coil. Makes no difference on the magnetic path outside the coil. ... BTW, I used the term "core" when addressing Ampere's Law because of the motor context. It is actuall...
by major
Nov 05 2019 9:39pm
Forum: Motor Technology
Topic: APL's DIY axial-flux motor
Replies: 1077
Views: 97149

Re: APL's DIY axial-flux motor

... I think the answer is that these coils are normally used on motors without permanent magnets where torque comes from reluctance (Swichted Reluctance Motors) and so the entire winding, no matter in which direction it goes, contributes to torque. ... here is the source: https://things-in-motion.b...
by major
Oct 24 2019 8:57pm
Forum: Motor Technology
Topic: Same debate again, motor windings!
Replies: 96
Views: 6076

Re: Same debate again, motor windings!

Punx0r wrote:
Oct 24 2019 5:28pm
sn0wchyld wrote:
Oct 24 2019 4:57pm
end turns are still contributing to usefull flux
Are they?
No.

Been through this on this forum before. I'm not too familiar with this forum search feature. Some recent white papers on the subject show negligible results. Or study Ampere's Law.

Regards,

major