Garry Stanley Pulse Motor

[woopy]

Yes Gyula

i mean 20 to 40 ohms per coil

so if i get an average of let's say 30 ohm per coil. So i make the following math
U= RxI that is 200volts = (18 x 30 ) x I or 200 devided by 540 = 370 ma

or200 volt s X 0.370 = 74 watts
My procedure is the following, as i don't know the possibilities of the 18 coils , i do the test on 1 single coil. So i consider that i will have more than 220volts in the final proto. So 220volts divided by 18 gives about 12 volts per coil.

So now i am testing the power on a single coil under 12 volts and i can feel in my hand the different force depending of the wiring and magnets etc.. very simple and practical way. And than i imagine the torque that will produce the all 18 coils sandwicthed together and my aim is to get not too much torque because my setting is probably not able to sustain enormous torque at the present . So i have a fiable working system to make the measurement of the IN. (ian-newmann) multiplyer.
See what Tyson sayd in his previous test , those neomag are capable of incredible power and can deform everything if not properly dimensionned.

Please i will apreciate your comments


good night

Thank's and goog luck at all

Laurent

[garrys]

ok let me try this another way forget about the windings take a coil and connect it to a meter perhaps one that reads amps so you can see the difference between current direction in this coil when you pass a magnet by it.
First try a north pole and then a south and note that the direction of induction changes for each pole relatively.

Now repeat this experiment again but this time use only a north pole but first test the end you have already tested and then test the other end

What you will find is that when a north pole passes the other end of the coil it reverses the flow in the coil just as having a south pole at the first end did.

if you now change the wires on this coil you can pass the north pole at the second end and get the same result as you started out with at the first end.
in order to achieve this you must now be causeing the induced flow in the coil to be traveling in the opposite direction though the function of the coil remains the same .

im going to address something ted said about output and speed not being related here while i think about it.

If you have a car motor doing 1000 rpm and you increase it to 2000 rpm you may not have doubled its output but you sure have increased it ...just as you are all finding more coils which actually equals more pulses equates to more output per rpm and so it also rings true that more speed equals more pulses per minute and even though these are lessor pulses due to shorter on times they still equate to an increase in output, at a guess about 50% per doubling of the speed and so speed is the key here, to more you have the easier it is to use by simply gearing it down to create torque at the output shaft

The output is actually the pulse power times its duration times is number of pulses per minute.

Garry

[gyula]

Yes Gyula

i mean 20 to 40 ohms per coil

so if i get an average of let's say 30 ohm per coil. So i make the following math
U= RxI that is 200volts = (18 x 30 ) x I or 200 devided by 540 = 370 ma

or200 volt s X 0.370 = 74 watts

Hi Laurent,

Your current and so your power numbers are in fact peak values of course because the 370mA current flows in the moments of the switch-on times and will be interrupted 18 times during one full turn of the rotor, ok? Also, you have to consider how long the switch is kept ON (this is the pulse width) at each switch-on event?

Earlier you wrote:
The attrapulsion mode is the fact to fire the coil when the pair of magnet is exactly centered above the coil. So if the coil side is eg N, than the S pole of the magnet will be attracted to the center of the coil and the N pole will be simultaneously ejected outside the coil. So for one pulse you get 4 working units (2 on each side of the coil).
So the magnet diameter (or width) must be about 1/3 of the coil diameter. I will do some test if this config is better than only on bigger magnet per coil.

If you choose the switch is on "for just a moment", i.e. for one unit of time, then your duty cycle is 18 interrupts divided by 360, (360 is one full rotor revolution in degree) this gives (18/360)*100=0.05*100=5%, this is the smallest value for it. With such a duty cycle the average current is 370mA*0.05=18.5mA only, so the input power is 200V*0.0185A=3.7W.
If you keep the switch ON for "longer than a moment", then your duty cycle hence current consumption increases, reaching the full 370mA value when the duty cycle is 100%. Suppose you keep the switch ON for 2 units of time, then duty cycle will be (2*18/360)*100=10% and so on.

Recalling what Ted wrote in his post on his coil design suggestion for you:
The pulse width should be the same as the distance (number of radial degrees) between the magnet centers.

So when you know already the distance between two magnets within one magnet pair, it will determine the "number of moments" for the ON time, and the real duty cycle could be figured out pretty well, hence the input power.

My procedure is the following, as i don't know the possibilities of the 18 coils , i do the test on 1 single coil. So i consider that i will have more than 220volts in the final proto. So 220volts divided by 18 gives about 12 volts per coil.

Sounds ok for me, assuming more or less identical DC resistance coils.

I ask what distance you plan to maintain between two facing magnet pairs?

To Garry: Thanks for the answer and I will digest and test your suggestion tomorrow.

rgds, Gyula

[woopy]

Hi Gyula

Thank's very much for your comment

You are fully right about the duty cicle. 3.7 watt is very small.

I have ordered the magnets this morning. they will be 20 mm / 10 mm and 2mm and are N45 the space between the magnets on the holders will be 10 mm. So they cover exactly the diameter of the coil (30 mm with a 10 mm air core center ) The proto i have wound today with a 3 mm diameter copper is 8 mm width. and are 7.2 ohm and 3 mh about 400 turns.

I have ordered twice the necesary magnets so i can simply add a second stage of magnet to reinforce the flux if necesary or for pure comparison sake.

Now if i make the calc if i decide for the 3mm copper (that i already have here ) and following your calculation i get

220 volt devided by (18 x 7,2 ohm). =220 /129.6 =1.697 A x 220 =373 watt

and now 373 watt x 0,05 = 18.67 watt average.So already much better than 3.7.

I will wait another day to make up my mind before coiling



Thanks

Laurent

[gyula]

Hi Laurent,

Thanks, and here is what I am curious too:
what distance you plan to maintain between two facing magnet pairs in one U shaped holder?

and what is the approximate distance between two adjacent U shape holders?

From these data the input power could be better estimated, it will be higher than 18.67W because the 10mm distance between two magnets within one magnet pair will lenghten the pulse ON time.

Thanks, Gyula

[woopy]

Hi Gyula

the distance between the U shape will about the width of the coil (about 8mm) plus 2 spaces of 2mm that is about 12 mm. But i hope i have not to increase this space because wobling.

The distance between the holders (which will be 32 mm bright) is the distance between the spokes (about 3.5 cm ) and the diameter of the center of magnet and coil will be about 46.4 cm.

OK thank's for input

Laurent

[Ted Ewert]

@ Laurent, Your coils seem about right to me. You'll find that the total amount of power you expend will be a lot less than the amount you calculated once the motor gets moving. This is because the impedance of the coils will increase with the switching frequency.
I suppose you can adjust the duty cycle of the drive pulse with a reed switch by varying the distance from the trigger magnet. However, if this is not accurate enough you may want to set up an optical switch.

Here is the current plan for the motor I'm building. This drawing shows the rotors superimposed over the stator coils. I'm also planning on putting a magnet in the core of the coils but I haven't worked out all the details yet.




Cheers,

Ted

[SkyWatcher]

Hi folks, Hi garry, thanks for your comments, do you wish to share your other ideas, if so, you are welcome to. Hi Ted, thanks for showing your new design, what function will the magnet in the core have and do you mean within a ferromagnetic core or just within a coil, thanks. I have come up with a solution for now, to remedy the flexing rotor issue. I will use the other 3/4" thick particle board rotors since they are much more rigid and drill 6 more holes to make 12 total and since i only have enough magnets to make 12, 3/8" thick stacks, for now I will mount them in the wood rotors in alternating fashion, then I will test motor with out any flux back bridging. Then, I will use steel washers to fill the voids behind each magnet stack and act as flux bridges with the steel disc saw blade attached to back of wood rotor making contact with steel washers. Then later when I can get more magnets, I will fill in the voids with magnets. This way I can see the difference in torque with the alternating magnet setup and see what the difference is with the flux back bridging and without.
peace love light
Tyson

[woopy]

Hi Ted

Wohoww nice design. Do you wound your coil yourself or did you find them already made somewhere ?

I am now waiting for the magnets and magnets holder. I will begin the lathing of the coils .

Thanks for the advices

good luck at all

Laurent

[Ted Ewert]

Hi Ted, thanks for showing your new design, what function will the magnet in the core have and do you mean within a ferromagnetic core or just within a coil, thanks.
peace love light
Tyson

It's going to be an iron core with a magnet contained within. Normally the magnet's field will be contained within the iron, except when the coil fires. Then it will hopefully be available to do some work.
A magnet isn't just like a garden hose where it can be turned off and on. It has to have some very specific conditions in order to do work. It seems to require moving magnetic fields, just like a generator, in order for its field to be utilized in a motor type mechanism. Switched permanent magnet fields can act very peculiar sometimes.

Cheers,

Ted

[Ted Ewert]

Hi Ted

Wohoww nice design. Do you wound your coil yourself or did you find them already made somewhere ?

I am now waiting for the magnets and magnets holder. I will begin the lathing of the coils .

Thanks for the advices

good luck at all

Laurent

Thanks, I always wind my own coils. That way I get just what I want. Besides, they're a lot cheaper and easy to make.

Ted

[woopy]

Hi ted

You are right , it is probaly better to make ourself exactly what we need than expecting and loosing a lot of time to look in all catalog.

And now let's go to the drilling of the rim yep that will be a hard job to be as exact as possible.

By doing this , i understand very much ,why there is much more people who are speaking and so few people who are doing.

My philosofical thank for the day

Laurent

[SkyWatcher]

Hi folks, here is the modified dual rotors with 12 magnets per rotor in alternating magnet polarity. Will be making some tests with these rotors, then try with a flux backing. Hi Ted, thanks for the information, are you planning on using like magnet poles facing each other and then repulsion away from core.
http://a.imageshack.us/img825/293/12...natingpole.jpg
peace love light
Tyson

[Turion]

SkyWatcher,
I thought I read somewhere that you needed to have a distance equal to the diameter of the magnets you are using between the magnets in order to keep their magnetic fields from causing each other problems. Is this not the case? It doesn't seem from your photos that they are that far apart.

Here's something I discovered that may help some of you with your builds.
I have had a hard time building larger rotors with more magnets on them because I only have a small drill press and there there isn't but about 5 inches between the support post and the drill bit, which limits me to about a 9 inch rotor by the time I drill it and put it on my bench grinder to assure it is perfectly circular. I got frustrated with this the other day, but that straight center hole is essential if you want a rotor that won't wobble, and dang near impossible to do with a hand drill. So I cut out my big round rotor out of cutting board material. Marked the center point and drilled a pilot hole with a medium size drill bit by hand. Then I marked it with a black felt marker so I could see it easily. I took the fence off my small router table and put a half inch router bit in the router. I raised the bit just enough above table top level that I could lay my big circle on it and move it around until I could feel the tip of the bit drop into the router hole. Then I clamped the rotor to the table with some hand clamps, turned the router on, and from down below I lifted the router up until it cut all the way through the plastic cutting board material. I used a 2x4 to easily lever it up once I disengaged the manual "brake" that holds it in place. It takes a little more work, but now I have a straight, true hole through my rotor, and I've got it all set up to do it again and again.

I also moved my grinder so one end of it sticks out past the side of my work bench. That way I can put my rotors on the bench grinder in place of the grinding wheel (Which is why I use 1/2 inch shafts on my builds---same size as the shaft on my grinder.) and use various files and sandpaper to make my rotors smooth and perfectly round.

Once the center hole is cut and they are perfectly round, drilling the holes for the magnets around the outside is easy on my small drill press.

[rave154]

turion...youre last photo ( the one on the right )..


a Classic Work Bench !!.... a coil on its side....a coil on its end.. a screw driver.....a ruler...a tube of glue ( on its side ! ) a pencil (all at different angles ! )....an open box of bolts.

all together now......"been there...GOT THAT !"