@joe18370 I only got a few watts out of it, but that is more because my turbine couldn't put out more than that. I think it would be good for about 20 watts.
next question is that you are using 2 sets of windings, offset, for equidistant spacing, correct? So you have 4 wires coming out of your stator, do you series them? or rectify them separately? if each set is producing 3ph, what's the best way of wiring that to your rectifier?
@drewartturbine There are three coils with 6 wires coming out. Then I connected the tails of the coils (after checking them on an oscilloscope for correct phase angle) to for a "wye" configuration. After that, the three remaining wires go into a rectifier.
You are using 8 poles, and an equally divisible number of legs in your coils. I was understanding that best design is a 4 mag pole/3 leg ratio? This is what Hugh P. designs follow, but is it just for 3 ph? I have read a number of sources some say it's to prevent cogging, others that it's to do with some esoteric 3ph geometry, others that it's to make each coil set have an approaching magnet, an centred mag, and a departing mag, so that the waveform produced by the coils set is "flatter".
@drewartturbine You are correct. Typically, there are 4 magnets to 3 coils to generate the three phases. However, this type of coil relies on placing the coils "120 degrees" apart from one another to get the three phases.
@drewartturbine The "coils" I'm using overlap each other to get the phasing. That way, it is possible to make the gap between the magnets smaller and increase the field strength. Although, I really didn't make good use of that feature with this turbine.
a pleasure to watch you work! So methodical, and well planned. I wonder on a small dia turbine like that if it might work better to have more magnetic poles, would increase the number of changes of flux direction, and might cut down some of the end winding's.
Very nice editing too, thanks for the through detailing, but speed up where possible.
@sjh7132 That was it; just one bathroom cup full. There were a number of air pockets, but I was pleased that it appeared as filled out as it did. But it was a surprise too. I thought there would be dry spots.
beauty job on the whole unit, now we'll find out what i've always been curious about; how a large dia. inner pipe will effect the performance of the wings.
I wouldn't mind a row of those along a fenceline. one on every post should put out considerable power.
@itsandbits1 Thanks, now I have to see if I can make a good turbine to spin it. There are some concerns about the longevity of the epoxy joints, so that is another "wait and see." I was happy with the output though. And there is the opportunity to bring the magnets closer together to increase field / reduce turns / reduce resistance.
@itsandbits1 Yes! I already had the bond with the saw blades fail once; I think from a varnish on the blades. So I sanded them. Thanks for the note; I'll put it in the description to make it more visible.
@photolodge My preference is Blue, but that was already mixed with Yellow to make Green. And of course, Green as well as White are Michigan State's colors. I just couldn't use those colors. So Red was the logical choice. :-)
@Caleb6543 Sir, I have seen some peoples use iron core in the stators. what is the reason of this? can this generate more power with iron core.? reply pls...thanks.
@Heart111ful I have no iron experience, but here is the theory to the best of my knowledge. Total power potential is identical no matter which you choose so the issue is efficiency. The iron core, I think, lets you use less wire and less losses to internal wire resistance. But, the iron core creates flux losses such that the metal heats up. So you lose some benefit that way. I suspect starting spin becomes a huge problem with iron core (called cogging?). I had starting problems with friction.
Did you make three sets of coils because bending the copper in tighter loops is not possible or because there is a mathematical reason that three phases has some advantage over one phase?
@definitionofis I used three phases because it is more efficient than a single phase. A single phase produces voltage peaks, and the peaks produce higher peak current which leads to more I^2R losses.
@Caleb6543 Correct me if I am wrong, since I am newly studying 3phase. RMS for 1phase is 0.71 RMS for DC is 1.00 so 3phase is in between at <29% savings of resistance. I think the overlap in the three coils wastes wire during the circumference parts compared to 1phase, which has no overlap. It would be interesting to see how much of <29% savings gets lost from that effect. A low ratio of circumference to radius of wire travel would minimize that loss; ie. long magnets on a drum is optimal.
@definitionofis I learned later, the current is sq root of 3 = 1.73 times more for 3-phase versus 1-phase. So resistance is 1/1.73 = 58% and that is like using 42% less wire (not 29% less). I have seen serpentine versions with overlapping windings, far from magnets, then coils might be better. I wonder if that inefficiency loses the benefit, too. (I'm just thinking out loud. I have no experience.)
so what is she puttin out,i am getting into this field now,building my own stators,good video
joe18370 1 month ago
@joe18370 I only got a few watts out of it, but that is more because my turbine couldn't put out more than that. I think it would be good for about 20 watts.
Caleb6543 1 month ago
made out of card board awesome man
superbungabunga 2 months ago
next question is that you are using 2 sets of windings, offset, for equidistant spacing, correct? So you have 4 wires coming out of your stator, do you series them? or rectify them separately? if each set is producing 3ph, what's the best way of wiring that to your rectifier?
drewartturbine 2 months ago
@drewartturbine There are three coils with 6 wires coming out. Then I connected the tails of the coils (after checking them on an oscilloscope for correct phase angle) to for a "wye" configuration. After that, the three remaining wires go into a rectifier.
Caleb6543 2 months ago
oops, just drew it out on paper and see, in my case it's the same as the mag array, 16 poles gets 16 legs. GREAT! Thanks
drewartturbine 2 months ago
Very Helpful! Thanks, I've been trying to understand the difference, so in a 16 pole rotor like I have, how many legs would you use?
drewartturbine 2 months ago
You are using 8 poles, and an equally divisible number of legs in your coils. I was understanding that best design is a 4 mag pole/3 leg ratio? This is what Hugh P. designs follow, but is it just for 3 ph? I have read a number of sources some say it's to prevent cogging, others that it's to do with some esoteric 3ph geometry, others that it's to make each coil set have an approaching magnet, an centred mag, and a departing mag, so that the waveform produced by the coils set is "flatter".
drewartturbine 2 months ago
@drewartturbine You are correct. Typically, there are 4 magnets to 3 coils to generate the three phases. However, this type of coil relies on placing the coils "120 degrees" apart from one another to get the three phases.
Caleb6543 2 months ago
@drewartturbine The "coils" I'm using overlap each other to get the phasing. That way, it is possible to make the gap between the magnets smaller and increase the field strength. Although, I really didn't make good use of that feature with this turbine.
Caleb6543 2 months ago
This has been flagged as spam show
a pleasure to watch you work! So methodical, and well planned. I wonder on a small dia turbine like that if it might work better to have more magnetic poles, would increase the number of changes of flux direction, and might cut down some of the end winding's.
Very nice editing too, thanks for the through detailing, but speed up where possible.
drewartturbine 3 months ago
Verry verry nice Vid man ! plain simple nothing more to add ... and no stupid music in the back ground it's a blessing ! ahahaha
MaN1aC666 4 months ago
Nice. You made the coils like I do. Less resistance that way :D.
20RoyalSuperKing 4 months ago
nice setup Caleb. i need me one of those nice socope...
regards
sam
emagnets 4 months ago
@emagnets Thanks. The oscope is a nice tool. 2 channels is okay, but it takes extra work to see what is happening with three phases.
Caleb6543 4 months ago
Looking at the scope output at 0:26, are there only two phases? or perhaps only two were connected to the o-scope?
skyl4rk 4 months ago
Thank you, I really enjoy your videos!
skyl4rk 4 months ago
@skyl4rk Thanks for watching! It keeps me motivated. :-)
Caleb6543 4 months ago
Can't wait to see it fly. Hope it works out. Good luck!
J2897Tutorials 4 months ago
Nice job. Was that one cup of epoxy all you used or where there more that you didn't show?
sjh7132 4 months ago
@sjh7132 That was it; just one bathroom cup full. There were a number of air pockets, but I was pleased that it appeared as filled out as it did. But it was a surprise too. I thought there would be dry spots.
Caleb6543 4 months ago
Beautiful design and construction techniques!
PoirierMike 4 months ago
beauty job on the whole unit, now we'll find out what i've always been curious about; how a large dia. inner pipe will effect the performance of the wings.
I wouldn't mind a row of those along a fenceline. one on every post should put out considerable power.
itsandbits1 4 months ago
@itsandbits1 Thanks, now I have to see if I can make a good turbine to spin it. There are some concerns about the longevity of the epoxy joints, so that is another "wait and see." I was happy with the output though. And there is the opportunity to bring the magnets closer together to increase field / reduce turns / reduce resistance.
Caleb6543 4 months ago
@Caleb6543
Just for anyone building with plastic; I do remember you saying you sandpapered and cleaned metal parts to get a better bond
itsandbits1 4 months ago
@itsandbits1 Yes! I already had the bond with the saw blades fail once; I think from a varnish on the blades. So I sanded them. Thanks for the note; I'll put it in the description to make it more visible.
Caleb6543 4 months ago
Nice job, cant wait to see some numbers. What color of play-doh do you recommend.
photolodge 4 months ago 2
@photolodge My preference is Blue, but that was already mixed with Yellow to make Green. And of course, Green as well as White are Michigan State's colors. I just couldn't use those colors. So Red was the logical choice. :-)
Caleb6543 4 months ago
@Caleb6543 Sir, I have seen some peoples use iron core in the stators. what is the reason of this? can this generate more power with iron core.? reply pls...thanks.
Heart111ful 4 months ago
@Heart111ful I have no iron experience, but here is the theory to the best of my knowledge. Total power potential is identical no matter which you choose so the issue is efficiency. The iron core, I think, lets you use less wire and less losses to internal wire resistance. But, the iron core creates flux losses such that the metal heats up. So you lose some benefit that way. I suspect starting spin becomes a huge problem with iron core (called cogging?). I had starting problems with friction.
definitionofis 4 months ago
This has been flagged as spam show
Did you make three sets of coils because bending the copper in tighter loops is not possible or because there is a mathematical reason that three phases has some advantage over one phase?
definitionofis 4 months ago
Comment removed
definitionofis 4 months ago
@definitionofis I used three phases because it is more efficient than a single phase. A single phase produces voltage peaks, and the peaks produce higher peak current which leads to more I^2R losses.
Caleb6543 4 months ago
@Caleb6543 Correct me if I am wrong, since I am newly studying 3phase. RMS for 1phase is 0.71 RMS for DC is 1.00 so 3phase is in between at <29% savings of resistance. I think the overlap in the three coils wastes wire during the circumference parts compared to 1phase, which has no overlap. It would be interesting to see how much of <29% savings gets lost from that effect. A low ratio of circumference to radius of wire travel would minimize that loss; ie. long magnets on a drum is optimal.
definitionofis 4 months ago
@definitionofis I learned later, the current is sq root of 3 = 1.73 times more for 3-phase versus 1-phase. So resistance is 1/1.73 = 58% and that is like using 42% less wire (not 29% less). I have seen serpentine versions with overlapping windings, far from magnets, then coils might be better. I wonder if that inefficiency loses the benefit, too. (I'm just thinking out loud. I have no experience.)
definitionofis 1 month ago