Garry Stanley Pulse Motor

[gyula]

Hi Laurent,

Nice job, I like it!

Your 18 coils will add up to 10.8 Ohm DC resistance and you wish to use a MOSFET switch that has a max 0.1-0.2 Ohm ON resistance, to minimize switching losses. If you need a type like that tomorrow I can help.
You wish to use a reed switch for controlling the gate of the MOSFET? Also, you wish to catch the collapsing fields energy of the series coils?

rgds, Gyula

....
And now a question about the coils.

What is a good config for 18 coils in serie
I intend to use my variac with a full wave bridge rectifier, so i can go from almost no voltage up to more than 250 volts DC.

I plan to make thin coils of about 30 mm diameter and a 10 mm center and about 7 mm width , which can accept about 100 turns of 0.5 mm copper wire.
A first proto of this coil gives 0.6 ohm and 0.11 mh
I would appreciate your input on this thema.

Thanks


OK good weekend at all

Laurent

[SkyWatcher]

Hi folks, Hi woopy, nice progress so far on your motor setup, I will be getting some materials for my expandable motor setup shortly. Hi garry, yes i agree with gyula, by all means, if you feel in your heart that you wish to share your other ideas freely with us, I would be grateful. You know there are many different people in this world, one just has to find those of like mind, so that things or ideas can be created in harmony and that place is here in my opinion.
peace love light
Tyson

edit: oh and thanks for the idea thaelin, i saw someone use those saw blades i think over at ou.com. that could work and a protective layer of duct tape or something could be wrapped over the find blade section. I'll have to check and see what the hardware store has, thanks.

[Matthew Jones]

For safety sake I would just cut the teeth off the saw blade. Forget the duct tape. LOL
At minimum most new saw blades come with hard plastic ring use it.

I've been carpenter all my life. I have seen the horror caused from a finger coming off more than once. It didn't look fun I wasn't thrilled having to hold on to one of them while I drove to the hospital with screamin bleeding fool next to me.

LOL Safety first

Matt

[Ted Ewert]

@ Laurent, I would recommend going with a smaller guage wire. .5mm is roughly equivalent to 20 AWG, and I would say 24 AWG (.2mm), or smaller would be better. You get more turns per coil, higher inductance, and with more voltage you get higher efficiency. If you want more torque, you can put half the coils in parallel (or more).
With the larger wire you are stuck with a relatively low inductance, even when they are all in series. Thinner wire gives you more options.
@ Garry, I don't think your crazy, I just don't understand your definition of back or forward EMF. I also don't understand how your coil could do what you claim it does. I'm not saying it doesn't work, just that I'm a little unclear about what it's effect is.
The best way to illustrate your theory would be with a demonstration showing the effects of your coil compared to a normally wound coil. This would go a long way in clearing up any misunderstanding.

Cheers,

Ted

[SkyWatcher]

Hi folks, Hit matt, thanks for the advice. Yes I was in carpentry for many years myself and saw many nasty things happen, like one guy nail gunning his fingers together and another falling off 2nd story and myself hitting my finger a couple times, ouch . I just bought 2, 7-1/4" plywood blades and am happy to see the hard plastic on the edges, I'll use these on my motor I have now to make some tests using 12 magnets per rotor. Hi Ted, thanks for your words.
Here is a pic of the steel disc rotor blades.
http://a.imageshack.us/img715/7293/s...laderotors.jpg
peace love light
Tyson

[woopy]

Hi Gyula

thank's for your help.

Untill now i (on my small motor setup) have used my old circuit from the Ossie motor. I enclose the shematic.

The idea would be to use the same circuit with a small 4.5 volt batterie to power the trigger circuit with the Hall sensor. Than the power circuit with mosfet would be feed by my variac through a bridge rectifier.
Of course if i can recycle the kickback it is better. I have tried as you can see a small circuit (fwbr) accross the coils.

I would fo sure appreciate your comment and prop

Hi Ted

Thank's for input

I am now wondering

I can buy finished coils of 0.2 mm they are about 16 mm width but have 110 meter of copper and gives 1 kohm for 760 mh.
Or the same with 0.3 mm at 4 ohm and 10 mh

what do you think. I don't need monster torque but enough to make a prony brake test and to determine the efficiency.

Hi Tyson yep good cutting oject be carefull

good day at all

Laurent

[gyula]

Hi Gyula

thank's for your help.

Untill now i (on my small motor setup) have used my old circuit from the Ossie motor. I enclose the shematic.

The idea would be to use the same circuit with a small 4.5 volt batterie to power the trigger circuit with the Hall sensor. Than the power circuit with mosfet would be feed by my variac through a bridge rectifier.
Of course if i can recycle the kickback it is better. I have tried as you can see a small circuit (fwbr) accross the coils.

I would fo sure appreciate your comment and prop

Hi Laurent,

Ok on your schematic, you could use it for this new motor control too, maybe the 100 kOhm resistor in series with the LED at the output of the Hall sensor is too high value, a 5.1 - 10 kOhm would be preferred? (these latter lower values should not increase current consumption too much from the 4.5V batterry, and I know it can work with the 100 kOhm but the switch-on and off time of the MOSFET would be quicker with the lower values. In fact a dedicated MOSFET driver IC would be here the best (but at a later stage) in case you find the captured bemf pulse energy from the coils is small.)

You use the IRF540, it is also ok with its very low ON resistance, the BUZ type is also good but it has only a 50V max drain-source voltage vs the IRF's 100V: use the IRF540.
EDIT: it is true the 44 milliOhm ON resistance for the IRF540N comes at a 10V gate-source control voltage and you have only hardly a half of it, it is surely well under 0.1 Ohm from the 4.5V.

Here is a schematic to capture the pulse energy from the collapsing field of a coil and at the same time add it to the supply voltage:
http://www.energeticforum.com/renewa...html#post56075

If you maintain a reasonable mechanical building accuracy with the positionings of the coils and magnets, then the collapse from each coil may be able to add up without much loss, so no need for using 18 individual capturing components for each coil. The circuit by Peter is explained in his post. Of course, you can find such capturing circuit from Ossie too, he recharges his run battery with it, if you want to use a variable power supply then you cannot recharge it of course, this is why I show Peter schematic.

EDIT: of course you can still use your Hall device and 2N2222 transistor circuit to control the IRF540's gate-source, and all the other parts of the schematic can come from that of Peter's, ok?

rgds, Gyula

[Ted Ewert]

@ Laurent, 1k ohm sounds way too high. Are your wire sizes in diameter or cross sectional area? .2mm in cross sectional area is equal to 24 AWG. They both have a resistance of about 84 ohms per km. This would make a 110 meter coil somewhere around 10 ohms, which sounds much more reasonable.

Ted

[Matthew Jones]

Here is a calculator for wire resistance

1 km = 3280.9 ft

Matt

[woopy]

Hi Gyula
thank's for input

As i intend to go up to 250 volt do you think that i should use a bigger Mosfet .
I have here some IRFP 450. And in this case do i change someting in the trigger circuit. And as per your EDIT do you think that i should go up to 10 volt for the trigger circuit ?

I can also use reed switch instead of Hall sensor to trigger the fet, and in this case what would be a good and simple circuit for the IRFP 450.

Thank's

Hi Ted

I enclose here the pix of the coil.
Surely there is a problem with the definition and AWG and mm diameter and mm2.
It is written ( 0. 2 mm2) which should be 0.5 mm diameter that is AWG 24 as you described. But in fact it is surely 0.2 mm diameter which should be 0.0320 mm2 or AWG 32.

But my problem is that next week i will order all the matos to make the coiling and magnet, so my question is.

Is a resistance of about 10 ohms a good choice to begin.
And if yes, tomorrow i will wound some different copper on my 30 mm diameter coil untill i get those 10 ohms.

What do you think ?

Thanks Matt for the panel of conversion.

Thank's at all

Laurent

[SkyWatcher]

Hi folks, Hi woopy, well if that it 32 gauge at 1000 ohms, then the coil length is around 6000 feet. and if your coil is 1000 ohms and you put all those in series, you wont get much speed at 250 volts. Here is a link to a nice web page of wire charts.
Wire Gauge: Nikola Tesla Page
I will be mounting magnets to my steel discs today, will probably use a little bit of super glue and thin strapping tape for a fail safe around outside edge of magnets.
peace love light
Tyson

[gyula]

...
As i intend to go up to 250 volt do you think that i should use a bigger Mosfet. I have here some IRFP 450. And in this case do i change someting in the trigger circuit. And as per your EDIT do you think that i should go up to 10 volt for the trigger circuit ?
I can also use reed switch instead of Hall sensor to trigger the fet, and in this case what would be a good and simple circuit for the IRFP 450.

Hi Laurent,

Yes, the IRFP450 will be good, it is a 500V, 14A device with 0.4 Ohm ON resistance. No need any change in the trigger circuit, perhaps you could use a 9V dry (alkalyne) battery instead of the 4.5V, the Hall sensor is also ok. Keep all the trigger circuit as it was shown in your picture, except use 9V to run it. Even the series 100 KOhm is ok.

Surely there is a problem with the definition and AWG and mm diameter and mm2. It is written ( 0. 2 mm2) which should be 0.5 mm diameter that is AWG 24 as you described. But in fact it is surely 0.2 mm diameter which should be 0.0320 mm2 or AWG 32.

If you consider the 1.076 kOHm measured resistance, then it cannot be 0.5mm with 110m length... Here are two links to look up some data on gauges and resistances:

American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies and

Maryland Metrics: Wire Gauge Calculations

It says a copper wire of 0.5mm diameter (AWG #25) has a DC resistance of 0.0878 Ohm for one meter length, for 110m this gives 9.65 Ohm.

An AWG #32 wire (it is a diameter of 0.2mm) has a DC resistance of 0.538 Ohm for one meter, for 110m it is 59.18 Ohm.

An AWG #44 wire (it is a diameter of 0.05mm) has a DC resistance of 8.7 Ohm for one meter, for 110m it is 957 Ohm, nearly 1 kOhm...

If you could check the wire diameter with a caliper, then you could try some calcs from the links; also you can suspect the real length of the wire on that 1 kOhm bobbin is something different from 110m...

Is a resistance of about 10 ohms a good choice to begin.
And if yes, tomorrow i will wound some different copper on my 30 mm diameter coil untill i get those 10 ohms.

MAybe the links can help you on narrowing the trial and error process... I think you could choose a single coil DC resistance anywhere between 3 Ohm to 10 Ohm. For the 18 coils in series the chosen Ohm value will be additive of course. Ted surely can give you more advice on the coils.

rgds, Gyula

[SkyWatcher]

Hi folks, oh well, had to test it out. The saw blade are not strong enough, i tested with just one rotor on the motor with 12 magnet stacks and the coils were bending the steel disc inward and making a lot of noise, i can only imagine how much it would bend them with both rotors on. Seems to use them, I'd have to use my old 3/4" wood rotors and use the steel saw blades on the back as flux bridges to prevent flexing. Oh well, at least I know alternating the magnets polarities on rotor and with the spacing fairly close like Ted showed works fine. I'll have to think up something.
peace love light
Tyson

[woopy]

Hi all

thank's Gyula ,so one point seems to be OK. (the circuitery)

Now for the wiring, i was pretty upset per what Tyson sayd and thank's to him i have to go in all the conversion tabelle to see that, as my LC meter is OK , that must be another failure . And i measured the wire diameter , almost unmeasurable but for sure it is nt 0.2 mm diameter but much smaller. So the sticker on the coil , showing 0.2 mm2 and 110 meter is wrong. It is much sure a 0.05 mm and 1500 meter.

So i have learned 2 things on this experience. First those big electronic retailer can make mistakes. And second thank's this mistake i had to make a lot of reflection to fix the problem, and by doing this i am now probably a bit more intelligent.

OK Gyula i wiil order a big coil of 0.2 diameter mm and wound myself the 18 coils. I think they will be around 20 to 40 Ohms.
So the calculation will give about 0.4 A at 200 volts average


Hi tyson

Whooowww the saw blade are bending and only on one disk. config

So you could sandwitch a cylinder of wood or plastic between the blades ,large enough to spend from the center axel to almost the very near of the magnets and coils. To make every thing rigid. But i have also experienced that when the timing is not "pico bello" the coils do not attract or repell the magnet but they push them outside with a lot determination,

hope this help

good night

Laurent

[gyula]

Hi all
...
i will order a big coil of 0.2 diameter mm and wound myself the 18 coils. I think they will be around 20 to 40 Ohms.
So the calculation will give about 0.4 A at 200 volts average
...

Do you mean 20 to 40 Ohms for one coil? or for the 18 coils?