Abilities using Permanent Magnet Alternators

Shaunpro3

New Member
Region
USA
City
Naples FL
So,
I have a EBIKE kit, 48v 1000w and trying to for 1 thing to extend my range and the speed I traveled as sure ya know, the faster ya go, the shorter distance able to reach.

So,
I recently learned of and bought a 48v DC PMA ( permanent magnet alternator ) and dreamed how wonderful it could be...

At 1st was dreaming of running my bike off the PMA w no batteries.
Then woke up a bit and determined that if could just keep my batt.s charged better , enabling greater range and better speeds I would be so happy...

I am now seeing it's not so easy !
So to not overcharge my batt.s , I got a charge controller and relay that are set to 55v low and 57.6v high.
I just got batt.s fully charged and I tested this morning going about 17 mph only to find I wasn't able to get as far as usual !
So charged batt s again and un hooked the controller & relay running PMA directly to batt.s .....as while riding I watched my voltage meter and noticed I didn't go fast enough to produce but about 48 - 50 volts ...so trying to do better I only went about 12 mph on way back,. Did make it home and still had some power left...

Not sure if ya know of these pma yet, I sure hope so..
I was wondering of relay wiring, passive or active, rather running the hot or neg. From pma to the relay,
My pma is a super core DC 2 terminal unit at 1800 amps max. And when used and has a load, the pma becomes harder to turn.

So, I am guessing my 1000w bike uses more power than can be made going the speeds I'm able to travel. Guessing. 🥴

If you have any suggestions or referrals I'm so grateful !
And today I thought of a diff. Way that may work better.
Instead of trying to reach power needed to charge my batt s with the pma,
Why not only worry of producing 12 strong volts, hook up a 12v inverter and run the household charger used each day..?

Guessing that prob. Won't work for reasons not considered...?

Again I Thank You !

Shaunpro3

Imagine that... i just spoke to a wise man and learned the only shot i have using this PMA is regenatrive Breaking and although disappointing its starting to make since in my head.

I would still like to to gather anyone's thoughts and/or ideas as to me, its such im able to use for mind fuel kinda and i thank you all for paying attention to me regardless !
 
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I'd like to see a picture or a link to your PMA. These things do have a purpose and it would be interesting to see its size and advertised capabilities.
 
thank you, online i saw those who power there hole house on one of these ! and i just figured out a answer to my problem... just have 2 batteries, 1 to run my bike and at the same exact time be charging the 2nd battery so that way when the maim one dies, just switch them around !
perpetual motion hasn't been beaten yet...lolol

 
You are trying to re-invent the Perpetual Motion Machine: https://en.wikipedia.org/wiki/Perpetual_motion
A device that produces more energy than goes in.
If you use the 1000 W motor to drive the PMA, thermodynamics says losses in the system will cause energy to decrease on the battery all the time. People argue with science all the time these days, but there is no profit in it.
If you want to use the PMA to charge the battery without using the motor, then you have invented a human powered battery charger. Inefficient, but has it uses, say to run a radio on a south Pacific island with plenty of breadfruit & coconuts.
If you just pedal a 1000 w direct drive motor unpowered, you'll find they drag pretty significantly with no power at all. I have one, and parked it in the garage for that reason. I pedal unpowered about 80% of the distance, except days when a >13 mph wind is in my face. I use a geared hub motor that doesn't drag unpowered. Doesn't have regenerative braking, either.
Enjoy your PMA.
 
your right and am being told the same by all but...! i just figured it out... the only answer to solve my problem is to have 2 batteries, one to power the bike and the other to be charged during..
then switch them ... over and over... what ya think of this wonderful solution my mind proposes...? just finding a answer that solves my issue when there is no other seams so good to me.. lolol
 
You will put less power in the second battery, than comes out of the first battery driving the motor. Laws of Thermodynamics. Unless you put a lot of leg power into it. In which case, why have a motor? You can turn food into electricity! BTW food is not cheap.
As a device to be driven by wind turbines, as the ad says, the PMA has possibilities. Energy in the wind comes from the sun, doesn't come from a battery.
When D cells were expensive pieces of garbage, 50's & 60's, people sold bike headlights that were powered by a generator on the front wheel. The D cells always leaked and destroyed the headlight, so was a winning proposition in those days. 50 watts is something a human can put out without sweating hard. 50 watts does not drive a bicycle very far, more like 250 is what fit humans put out.
 
when going about 12 - 15 mph, it puts out around 40=50 volts and i can ride a while on 1 batt, not sure would charge #2 completely, but will be better than nothing..
and heck with producing enough volts to charge #2, just produce 12 strong volts which will run a 12v auto inverter allowing my home charger to be used to charge #2....!?!?!?!?
 
another question please...
at 1st, with the charges i used then, when i charged my batt.s all the way it took about 6=7 hours.....
so then i need a new charger and got one.... one practically the same as before. for a 48v battery pack... so this new one is again 48v 2.5 a but yet today, once batt.s died and i plugged in this new charger, about 1.5 - 2 hours later the charge light was off indicating a full charge....??????????
is that possible, or does that indicate a battery maybe dyeing or something else responsible or does it now charge in a 1/3 - 1/4 of the time required before../?????
 
"Battery died" means perhaps the controller dropped out because it thought battery was below minimum voltage?
You are checking your charge with a DVM? One that is calibrated from a reputable source? I use newark.com DVM myself. I've checked calibration with new On semiconductor zener diodes.
Or are you checking your charge with the little battery symbol on the bike display? Which many people have complained is not accurate.
My 3rd throttle came with a meter built in, which when checked with my newark sourced DVM, seemed entirely accurate.
Maybe BMS is not charging everything evenly, but stopping charge after one stack charges up. One stack which has a problem. What brand battery from what source?
 
i use 4 L/A 12v batteries, and have level meter built in the throttle and a digital v indicator but how i knew they were dead today is because the bike motor was clicking off as it normally does, then going very slow to make it to my destination....they were pretty dead and had left plugged in all night last night, fully charged this morn....
 
Lead Acid batteries when overcharged can dry out and lose capacity. Auto or Motorcycle service lead acid batteries are not made to be deep cycled, as you have stated you have done. These are not sealed lead acid batteries, are they? Some of those are sold as deep cycle batteries.
Batteries in series without a special charging arrangement can develop a problem with one of the batteries that makes the whole stack seem bad. Laptops sense every cell in the pack to stop charging if one cell goes bad, to prevent damage. My Dell laptop battery had 8 terminals. Most LiIon bike batteries use BMS to equalize charging. Some are more successful than others.
Two or 3 people have had successs with this attractively priced battery: https://electricbikereview.com/forums/threads/is-this-battery-pack-for-real-106.43001/unread
If you are looking for a replacement. If I bought from ali I wouldn't send them my real debit card #. I'd buy one of those one time use cards.
 
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