Author Topic: Hoverboard motors! (Read 4407 times)

GreenTeam · « **on:** July 15, 2020, 05:52:21 AM »

I picked up some hoverboards for dirt cheaP!! Five or six complete ones and I think ten more wheels. Which, the wheels are where the motors are. These ones are the 4.5 inch version. Which if I'm right comes with 20 magnets and 18 teeth on the stator. And it's wound with 2 wires at once. It's 3 phase . I would throw pics up but I can't yet I don't think. Would anyone use these as they are or rewind them ??. I am thinking of making one into a axial flux with magnets and wires. Is that possible,?

GreenTeam · « **Reply #1 on:** July 15, 2020, 06:22:01 AM »

The stator to the hoverboard motors
And.also a picture of an winding calculator I found. Do I wind like this winding scheme says or is this differant?

electrondady1 · « **Reply #2 on:** July 15, 2020, 07:15:06 AM »

looks like an excellent score

GreenTeam · « **Reply #3 on:** July 15, 2020, 07:49:52 AM »

Is it possible to take the wire and magnets out and convert it from radial flux to axial fluX? I only ask because I think coreless may be easier to produce power. On a multimeter it produced easy 4-8 volts hand spinning. And on the 10 amp circuit it produced a full ampere....hand spin. Also, part of the buy of the hoverboards came the circuits which is something like 63v 220uF caps and voltage regulators I think. Is there any way to incorporate into a pma?
Also, I am thinking of taking just a few sheets of the stator for the stator core during the resin pour to maximize gains. I want this for wind power. To be a cell phone charger mostly. So small, highly portable, , zero cogging, and 12 volts and 100 watts output .

mbouwer · « **Reply #4 on:** July 15, 2020, 09:50:22 AM »

Can you neatly release the coils from the hoverboard motors?
Then you may not have to wind coils yourself for a stator of an axial direct drive generator.

mbouwer · « **Reply #5 on:** July 15, 2020, 10:42:53 AM »

I now have a stator with 45 self wound coils.

Mary B · « **Reply #6 on:** July 15, 2020, 03:44:09 PM »

I would use it as-is. Put 2-4 on the same spindle and drive the magnet rotors all together. I am thinking at 200 rpm you are going to easily see 18 volts so charging a 12 volt system would be easy. Could series/parallel for a 24 volt system.

Scruff · « **Reply #7 on:** July 15, 2020, 06:36:05 PM »

Oh Shoot!

....I'm in the totally wrong thread....

GreenTeam · « **Reply #8 on:** July 16, 2020, 06:20:34 AM »

Quote from: mbouwer on July 15, 2020, 09:50:22 AM

Can you neatly release the coils from the hoverboard motors?
Then you may not have to wind coils yourself for a stator of an axial direct drive generator.

No I cannot release them. But , my experience with hoverboard stators is...
The wires are wound such that there are perma bends in the wires. It's easy to unwind them and recoil into axial flux I imagine

GreenTeam · « **Reply #9 on:** July 16, 2020, 06:25:18 AM »

Quote from: Mary B on July 15, 2020, 03:44:09 PM

I would use it as-is. Put 2-4 on the same spindle and drive the magnet rotors all together. I am thinking at 200 rpm you are going to easily see 18 volts so charging a 12 volt system would be easy. Could series/parallel for a 24 volt system.

Do you mean to out 2 or more of these stators already wound on one axle and the magnet rotors on also? Like a stack of pancakes? How much power would I be able to extract from one motor? And what if I use a 2:1 step up gear?

Mary B · « **Reply #10 on:** July 16, 2020, 03:00:35 PM »

Stack complete motors on a common shaft, no mods not changing wires around... just the motor to motor wiring to determine voltage output. I am guessing your magnet rotors are the part that turns just like in the F&P washing machine motors. your stators will all attach to each other then make brackets to attach all the magnet rotors to each other so you have 4 complete motors stacked. Your blades attach to the magnet rotors. I suspect the bearings in these are pretty wimpy so I would do a jack shaft to your blades and that shaft can then drive the magnet rotors via a flex coupling.

Hard to describe... I would need to have one in my hands...

SparWeb · « **Reply #11 on:** July 16, 2020, 03:16:48 PM »

First things first: watch out - you're going to magnetize all your tools!

I second the vote by Mary: connecting these motors in a gang is the way to go. There are several ways to go about it. You can rectify each motor into DC, then "stack" the DC in series. Should get some amps at a good voltage. Or connect the motors in parallel and then rectify just once, getting for yourself a lot more amps if you only need a modest voltage.

The other point about the bearings is something you can sort out later - but yes, you should mount a propeller blade on a shaft separate from the motor's shaft.

Important details before everything gets taken apart:
What battery is used in the board?
Did you keep the electronics?

GreenTeam · « **Reply #12 on:** July 17, 2020, 01:53:23 AM »

I got a bucket of these motors! Plus I acquired 5 complete ones minus the charger. I bought them because I figured that I am not going to get the battery packs , some useable electronics ( which I can barely solder ) lots of enameled magnet wires and least but the most important 200 neodymuim magnets in total ( for 200 ). And after buying this , I'm in deep wheel and my partner laid down the law and told me I got tops maybe 2-3 weeks to produce a wind turbine thwt can power up a few tablets. But I ran into a serious issue that is not on the 6.5 inch version. First being, I can't seem to completely remove the plate to open it up. There is a strange rectangular black metal block attached to the end of the axle and I can't get it off. It looks like it is threaded, but , from what I've seen from millennial engineers ....... I have quite a few circuit boards for them , looks like axles with bearings, and battery packs that look like 18650 for sure. I kept the battery pack from the 6.5 inch version I tore down. I don't understand about mounting a few into parallel and then bridge rectify once. And what happens if I magnetize my tools? I take it this is bad? I am worried about my multimeter and micrometer, as cheap as they are ( crappy tire ) I can't get replacements for a month or so at a time. I know, I don't know Jack #&$8$( about what I got myself into, but , the way the economy , climate , country , job security is.going , I wanna be prepared to live off grid totally one day.

SparWeb · « **Reply #13 on:** July 17, 2020, 02:41:14 AM »

There's two sides to this:
One, we have a DIY site here, so we do hope you are trying to do it yourself, which includes the learning. Even if we could coach you through every step of a build (we can't, we've tried) then you'd be hopeless to change or improve anything or solve any next little problem that comes up. So we'd all be frustrated by that. Time pressure also doesn't help. It makes the learning forced and impatient, rather than thorough and understanding.

Two,
The "nut" actually seems to be a snap ring, except it's made from sheet with tabs that drop into a groove around the shaft. Removing that will be a pain. Try prying it off like a bottle cap if you have to remove it.
You have machines that work. Try not to ruin them just to take them apart - but you do have spares, which gives you room to make mistakes. Learning from mistakes sometimes is the best. Keep those boards. You can learn a lot by examining them carefully and learning what's on it and how it's connected. Later, you may be able to tear some down for electronic parts, too. When I got started with this stuff, I spent years just taking things apart because I knew I didn't know enough about how it worked, or even how to recognize the pieces. Time well spent.

SparWeb · « **Reply #14 on:** July 17, 2020, 02:41:50 AM »

Magnetizing tools is annoying, that's all.

Adriaan Kragten · « **Reply #15 on:** July 17, 2020, 04:40:23 AM »

Using this kind of PM-motors as wind turbine generator has two major problems. It is assumed that the motor has a 3-phase winding which is rectified by a 3-phase rectifier and that the generated DC current is used to charge a battery (for rectification of a 3-phase current, see my free public report KD 340).

The first problem is that the generated voltage is much to low at the rotational speed range which is used as wind turbine generator to charge even a 12 V battery. This problem can be solved by rewinding the coils with thinner wires and more turns per coil. It might also be possible to modify the existing coils such that turns which were originally connected in parallel, are now connected in series. But this is a lot of work and you must know very well what you are doing. Another option is to use a DC-DC converter which increases the voltage and decreases the current but most standard DC-DC converters reduce the voltage and I don't know if the required inverter is available. Another option might be to use a 3-phase transformer and to increase the AC voltage.

The second problem is that normally there is a ratio 4 / 3 in between the number of magnets and the number of coils. As a coil contains an iron stamping, this means that there is a position of the armature for which a large number of magnets is just opposite a stator coil. This is a preference position because the magnetic flux flows easiest for this position. Because of this preference position, there is a large peak in the clogging torque and this peak results in a high starting wind speed if you use the generator in combination with a wind turbine rotor with a low starting torque coefficient. So before making any modification, you should measure the peak on the sticking torque and check the starting wind speed for the wind turbine rotor which will be used. The starting wind speed can be calculated using formula 8.6 of my free public report KD 35.

GreenTeam · « **Reply #16 on:** July 18, 2020, 04:27:56 PM »

As Sparweb stated, the rings are a real pain to get off, yea!. But, I do have a tool that spreads them apart! Tools is one of the things I have no shortage of. Time, patience and absorbing knowledge is other things to my advantage. I do understand things like faradays law, resistance, Positive/negative etc. And also, I understand the 4:3 magnet to coil ratio. I am unwinding all the enamelled magnet wires which is 2 wires @ 0.5mm per phase, As I unwound, I counted 25 or maybe 27 winds per slot. And one phase was 6 teeth in total. Well, I am converting the motors to axial flux, 6 coils. And, I can do 3 magnets per stack. And that means I am short two magnets or have 2 left over. As for power, it did generate 1 ampere but was really hard to turn, I can put another one back on a multi meter and take a pic, it produces about 4 bolts hand spinning, So, it will hit at least 12 volts I suspect at higher RPM. The magnets, using K and J magnetic site calculator, rates them at least N42. But, i messed up on converting my fractions and really, the magnet is half the thickness than what I input the magnet calculator. So might be close to N50? They are freaky strong regardless. And, I am going to use steel metal discs that are used for electrical junction boxes.
I sure do appreciate all the help I can get, As right now, I modded a dremel router attachment to build a circle cutter tool with a dremel using diamond bits.
I know what I am doing may be unconventional, but, the axial flux topology has a lot of room for error

GreenTeam · « **Reply #17 on:** August 16, 2020, 09:51:43 PM »

Quote from: Mary B on July 16, 2020, 03:00:35 PM

Stack complete motors on a common shaft, no mods not changing wires around... just the motor to motor wiring to determine voltage output. I am guessing your magnet rotors are the part that turns just like in the F&P washing machine motors. your stators will all attach to each other then make brackets to attach all the magnet rotors to each other so you have 4 complete motors stacked. Your blades attach to the magnet rotors. I suspect the bearings in these are pretty wimpy so I would do a jack shaft to your blades and that shaft can then drive the magnet rotors via a flex coupling.

Hard to describe... I would need to have one in my hands...

So far, after scrapping a wheel for everything that can be upcycled, i was left with a stator on a axle. The axle appeared to be held in by a little ring. After removing it, the axle would not come loose. I think its pressed in while hot. Also, i am having issues taking the bearing out. If anyone has anyone tips, i am all ears!

MagnetJuice · « **Reply #18 on:** August 17, 2020, 01:00:21 AM »

Are you sure that you want to remove the shaft out of all those motors? It would be a lot of work and then what are you going to do with them?

If your motor is like this one, a knurled shaft is pressed into the hole in the stator.

The shaft also has a key to lock it in place. Not easy to get it out without a power press. You could try to beat it out with a big hammer and a piece of round metal. I am not sure that it would worth the trouble.

It would be easier to build an axial flux alternator using the magnets from those motors.

Ed

GreenTeam · « **Reply #19 on:** August 17, 2020, 05:40:19 AM »

Quote from: MagnetJuice on August 17, 2020, 01:00:21 AM

Are you sure that you want to remove the shaft out of all those motors? It would be a lot of work and then what are you going to do with them?

If your motor is like this one, a knurled shaft is pressed into the hole in the stator.

(Attachment Link)

The shaft also has a key to lock it in place. Not easy to get it out without a power press. You could try to beat it out with a big hammer and a piece of round metal. I am not sure that it would worth the trouble.

It would be easier to build an axial flux alternator using the magnets from those motors.

Ed

reason being is this, the axle is already the correct size for the bearings in the hoverboard motors. And, i am on a seriously handicapped budget now. I am not allowed to spend any more dollars lol. So, yes , i am sure. I need the bearing and axle

for these. Easy to tell my first from my second. And i am going to ( geometry dictates ) do one up that is maybe 18-24 coils using 2x 0.50mm wire

. And 85 turns per coil. Star wired. Done my single coil tests and am happy so far. Just hung up on kitting out a free in every sense magnet rotor system now for my stators.

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Author Topic: Hoverboard motors! (Read 4407 times)