Search found 1351 matches

by Hummina Shadeeba
Dec 07 2018 12:33pm
Forum: Motor Technology
Topic: Some random high speed motor winding machines
Replies: 2
Views: 175

Re: Some random high speed motor winding machines

Is there a machine that will do a fat wire? None here.
Fat wire MAY get more fill but recently found that if I adjust the pwm frequency to 30,000 I have no audible noise but it seems to be getting into skin effect territory with a 17 aug wire i read. I want to stay at 30,000. Any experience?
by Hummina Shadeeba
Dec 06 2018 4:02pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

Thanks for all ur thoughts and info it’s been educational. Given the iron losses in the rotor are said to be relatively low I’m just going to try some wider magnets instead of the hallbach as so far bigger has shown better. Im already using .2mm lam stator. How do mellow boards get a totally free co...
by Hummina Shadeeba
Dec 04 2018 11:57pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

How much loss is in the rotor back iron vs the stator? looking at this first animation I don’t see the field changing in the backiron at all. Strong but not changing. Is this sim with low amps? https://m.youtube.com/watch?v=d7wTI2V3gb0 But looking at this it’s way out past the back iron https://m.yo...
by Hummina Shadeeba
Dec 03 2018 12:58am
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

By reducing eddies and hysties in the rotor then will be an easier coast no?
by Hummina Shadeeba
Dec 02 2018 11:02pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

7C7D8DB2-E429-461A-A98B-990B98EE3A46.jpeg I’ve searched the crap out of powdered cores and it’s not for me although with the right 3D shaping it could be good it shows https://pdfs.semanticscholar.org/c950/ba1a6213782d95258d58d90cd6ad2da7ab7a.pdf Need that high mag field and high torque. Thanks for...
by Hummina Shadeeba
Dec 01 2018 11:33pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

I already use .2mm lams. I forget the silicone percent. You think it would be worthwhile doing a powder core or will the hysteresis be the dominating loss anyway? Or a hallbach array seems an easy plus As it is now I’ll get maybe one amp for a no-load test at 7000erpm. (1000rpm) but things depend gr...
by Hummina Shadeeba
Dec 01 2018 5:49pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

tidelforce may have a motor that doesn't have noticeable ratchetting of magnets at very slow speeds that you would feel, which is nice, but really im trying to find how to reduce the drag on the spinning motor at all speeds while unpowered. Is this enherent with a permanent magnet motor? what kind o...
by Hummina Shadeeba
Dec 01 2018 4:01pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

C9DED185-DC4E-4500-8FEF-A77D306924C1.jpeg
C9DED185-DC4E-4500-8FEF-A77D306924C1.jpeg (247.36 KiB) Viewed 497 times
Yea are there any!!? :mrgreen: I’ve been looking for something to shoot for rr.. copy, and get some epdm stators made to try for skate hub motors.
by Hummina Shadeeba
Dec 01 2018 12:20am
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

Re: 4x less coasting resistance

Ooo du. Thank you

Looking on emetor could I equate iron losses to this resistance while coasting


But motors with more poles have less resistance while coasting but would have more iron losses for a given rpm with all other parts of the design the same no?
by Hummina Shadeeba
Nov 30 2018 5:52pm
Forum: Motor Technology
Topic: 4x less coasting resistance
Replies: 21
Views: 768

4x less coasting resistance

Maybe it’s old news and a thread somewhere but where is this used or why isn’t it? Less low speed control?

https://www.degruyter.com/view/j/phys.2 ... 08_fig_001
by Hummina Shadeeba
Jul 26 2018 3:23pm
Forum: General Discussion
Topic: Trouble With the Car You're Still driving?
Replies: 38
Views: 1099

Re: Trouble With the Car You're Still driving?

working in the night with lights is nice. no one can steal that from you.

why does marty get only one D battery by his name and i have two and his seems to have gone into thermal runaway?
by Hummina Shadeeba
Jul 26 2018 2:52pm
Forum: General Discussion
Topic: Trouble With the Car You're Still driving?
Replies: 38
Views: 1099

Re: Trouble With the Car You're Still driving?

sounds scary winching it up a hill solo as if something does go wrong and somehow something breaks maybe the car would go to town by itself with no one inside to put on the brakes.

you could call the store looking for a winch before walking the two miles. phones been round a while
by Hummina Shadeeba
Jul 24 2018 7:07pm
Forum: General Discussion
Topic: Trouble With the Car You're Still driving?
Replies: 38
Views: 1099

Re: Trouble With the Car You're Still driving?

please tell me what im denying even after you post it! sounds exciting. hope its not a letdown.
by Hummina Shadeeba
Jul 24 2018 5:57pm
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

i normally charge at close to the max charge rate but I dont know if you can figure it from looking above but they are not talking about pulses but seemingly full charge cycles much higher than the stated max charge current. thats the odd bit. ive heard of doing such things in the tesla and other st...
by Hummina Shadeeba
Jul 24 2018 4:02pm
Forum: General Discussion
Topic: Trouble With the Car You're Still driving?
Replies: 38
Views: 1099

Re: Trouble With the Car You're Still driving?

master of confusion lets see if we can figure you out "This from a snowflake who was chanting he didn't have one some 20 months ago..." Youre saying i didnt have a president "some 20 months ago" i guess. no i didnt say that but find me a quote you big game hunter. " Are you denying you posted in thi...
by Hummina Shadeeba
Jul 24 2018 3:52pm
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

the question ive been asking is what is the math formula say as far current to volume. everything else is hearsay. here's a study with scientific approach and id like to know what IT says is best. there are a couple other studies that have similar results and as fechter says this was a practice he's...
by Hummina Shadeeba
Jul 24 2018 12:51pm
Forum: General Discussion
Topic: Trouble With the Car You're Still driving?
Replies: 38
Views: 1099

Re: Trouble With the Car You're Still driving?

maybe you'll have to find a quote cause i dont think you'll find me saying ...whatever it is youre saying I said. I guess you moved on from your thread. too many snow flakes for you over there i guess. be strong
by Hummina Shadeeba
Jul 24 2018 11:14am
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

cell capacity certainly has to do with charge current. people dont put 100 amps into a battery with a 1ah capacity. i mean they generally dont and it's not recommended..except maybe here but whatever and we all know what we mean. more in parallel. more cells and more current goes in without heat. bu...
by Hummina Shadeeba
Jul 23 2018 8:24pm
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

yea lipo would be probably be a safer bet but the math seems to be missing something as its a volume to current conversion but the volume is based on a 2 dimensional surface it seems as if you were supposed to unroll an 18650 to figure out maybe. im more so just trying to figure out this math and se...
by Hummina Shadeeba
Jul 23 2018 4:11pm
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

if only i had a clue on the math. For a test all i would do would be following the charge schedule above and blasting my stuff with super high current for the right ratio of cycles and seeing what the overall mah shows going from 3.5 to 4.1. so many people are worried about going over the manufactur...
by Hummina Shadeeba
Jul 23 2018 4:00pm
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

ok i see what youre saying ...if you set regen so high it would just be increasing the braking force as well. i though something else. but about charging with high current as described in the study above and the screen shot I posted, it would be a full charge cycle at at least 9mA cm ^-2, infact up ...
by Hummina Shadeeba
Jul 23 2018 3:23pm
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

from what i read it seems if the cell is less than 50% state of charge it could take a lot more than the stated charge rate but forget regen....how about this weird high current "healing" cycling? what current would it be?

why would your wheel lock up if the regen was too high a current?
by Hummina Shadeeba
Jul 23 2018 2:40pm
Forum: General Discussion
Topic: how much regen is too much for the battery
Replies: 46
Views: 940

Re: how much regen is too much for the battery

following this high current healing regime would not be sticking to the recommended charge rate and is shown to end up with safer cells.