STEORN DEMO LIVE & STREAM in Dublin, December 15th, 10 AM

[Bruce_TPU]

bugger. I ordered those as I couldn't work out how to buy on Elna

Hi Jimboot,

To order from Elna, call them!   

Anybody see this on the Steorn public forum? It's a post from Sean McCarthy.

"The magnetic arrangement on the rotor is the same in both cases, an N pole above an S pole (or the other way around). The coils in the pulse motor (like the coils on the Orbo motor) are both facing up."

I already knew that.  If anyone had looked hard at the Clanzer/Steorn Units, you would see magnets in one that was put together and you would have seen black marked on end (North, Clanzer always marks N black...LOL) and opposite (black marks) from each other.  Thus I deduced N and S.    

You would not want to sit next to me and watch a mystery....LOL  You would not enjoy hearing the "who done it" five minutes into it...LOL

Cheers,

Bruce

[Airstriker]

NO Back EMF explained in original ORBO motor (sorry for lame pictures ):

First and second picture:

1) First stage

A are approaching the toroid coil. They are simply being attracted to the core. Coil's circuit is open. As the magnets "coupled" flux goes through part of the toroid's core this induces EMF in the coil - an electric potential difference across two open-circuited terminals. The current doesn't flow so there is no Lenz interaction with the rotor.

2) Second stage

Magnets reached TDC. Magnets "coupled" flux goes through half of the toroid. Or it's being divided by two - part of the flux goes left side of the toroid and the other part goes right side of the toroid. How it is in fact doesn't really matter.

As the magnets reached TDC, we close the electric circuit and fire up the current to saturate the core. As the core is partially saturated by magnet's flux we don't really need much current (this is the main and very important difference with JLN setup). In the first picture you can see, that the applied current made the the coil's magnetic flux go clockwise. In the second picture the coil's magnetic flux goes anticlockwise.

Now the important part. Why don't we see any Back EMF here? Simply because magnet's "coupled" flux will always choose the simplest way to go - the way it find's no magnetic resistance. So magnet's "coupled" flux lines will always align here with the coil's magnetic flux lines. In the first picture this "coupled" flux goes clockwise and in the second anticlockwise.
So as these flux lines does not "fight" with each other - we simply have no Lenz Law interaction here.

3) Third stage

As the magnets go past the toroid, their flux lines still align with the coil's flux lines but the aid they provide in saturating the core is getting weaker with the distance from the toroid. However, the current input (to keep the saturation) stays constant at some point (in fact very quickly) because of the core's material properties. Remember the graph "Amplitude Permeability vs. Flux Density" for Metglas? If not have a look at it below. What you find in this graph is: The higher the flux density, the lower the permeability. However for metglas the permeability stays constant between 0 - 0,47T. As the permeability is getting steady and constant, the current needed to keep the core saturated is also getting constant. This is exactly what you see on the scopes.
As the magnets move on, there is still no Back EMF because there is still no "negative" interaction.

At some point we open the coils circuit and the process repeats.

Third picture is just a side view of the first and second picture.

Also to point one thing - picture one and two does indeed show that the direction of current flow doesn't matter here.


Now one thing I must admit I was wrong about.
Have a look at metglas hysteresis loop. What's important in it is, that it has really high remanence (about 0,5T). Fortunately it also has high squareness ratio - low coercive force. That simply means that the resistance of a material to becoming demagnetized is low. High squareness ratio also means very high speed responses of the material. All these properties of metglas make me say the following:

- There is no sense in recovering the energy of the colapsing field, as much of it stays residual in the core (note, that residual doesn't mean that it dissipates inside the core as gravityblock says). Also note, that on their ORBO graphic presentations and animations there is in fact no recovering circuit.
- The fact that much of the field stays residual will not be a problem in any way, if we simply apply a very small magnetizing force in the opposite direction (going to the left on the hysteresis loop). To do it in ORBO is very simple. Just use the following magnets orientation on the rotor:

N S N S N S
S N S N S N

, and connect all the coils in series but in a way that every even coil is saturating the core in one direction, and every odd coil is saturating the coil in other direction.

This way we soothly move around the hysteresis loop with no side effects or energy loss.


So to be honest, the whole ORBO is nothing special. I mean it's briliant, but it does not violate any laws. It just uses material properties and proper magnetic flux "redirecting" to spin the wheel with very little energy input. Then they just get more energy output than input, simply utilizing the kinetic energy they gained. That's it.

By the way - please be my guest and test this theory in real life.

Ps. Of course the position of the toroid versus magnets is very important here. Also their dimensions.
PS2. Gravityblock, when will you start saying about UFOs here? I really cannot wait!

Best regards,
Julian S.

[PaulLowrance]

I also read over at Steorn, Sean saying that there are many types of Orbo that share the same principle, he mentioned mOrbo, eOrbo, and ssOrbo.

Cool, maybe there's hope for my tOrbo, worlds Tiniest Orbo just over 1" diameter  -->

http://www.youtube.com/watch?v=c8hZgxccWxo

[Jimboot]

Hi Penno,

Yes that is a hall vain sensor from Jaycar that I have cut the built in magnet off. This sensor is good because it can be powered with voltages from 4.5-30 volts.

I can post a circuit but it is not much different then the mosfet-hall sensor circuits shown by others.

The large toroid ofcoarse can be wound with more turns of thinner wire to reduce the current and increase the efficiency but my goal was to simply show a working concept motor.

To further increase the efficiency and torque of this concept motor the core must be laminated to reduce drag on the rotor.

Regards,

Ossie

I'm trying to use the JLN circuit but not having much joy. If you do get a chance to post your mosfet circuit I would be very grateful!

[Jimboot]

Hi Jimboot,

To order from Elna, call them!   


Bruce

Aaah I'm an online marketer as my day job so I get confused when there is no "buy" button & I'm in Melbourne Aust so the timezone thing usually gets me