Re: [EVGRAY] Re: Winding BiTT with C shape winding tool

Body

Hi Kone, Garry,

The reason for the correction is that the dot convention is at odd because of the different phase relationships. For a one phased transformer the dot convention tells that when the current enters a dot in a winding it exits the dot of the other windings. The windings are all wound in the same direction around the same leg (ring) and all windings have the dot at either the beginning or at the end of each winding. I.e. that's at the first (or last) layer end of each winding. For the UDT and BiTT (and the Bill Alek trafo and three legged trafos) this is true when seen from the primary. Each winding of the secondaries placed on other legs then has the current exit the dot end when entering the dot end of the primary winding. But the two secondaries are actually opposing each other when seen from their common ring (omitting the primary leg). Thus the dot convention is not correct when looking at only the secondaries alone. Current entering the dot end of one secondary (when used as a primary winding) will actually also enter the dot end of the other secondary when wound as shown in the figure.

Regards
Ole
 

---In [email protected], <onielsen@...> wrote :

 Correction in red and blue in text.

Hi Kone,

"And my question is "what is it" that splits the backemf magnetic forces from the forward forces, and this split enables the backemf to take that lower resistance route back to the opposite secondary in the BiTT transformer? Maybe just the proper time-delay?"

As the flux prefers the path having the least reluctance the reflected flux from the secondaries tends to take the path through the outer ring instead of going back to the center leg. When the windings of the side legs are connected in series and having the same turn numbers they share the same current to generate the same magnetomotive force (mmf) in each side leg. When the side windings are put in phase correction they are in opposition to each other (i.e. the dot end of one side connected to the no dot end of the other side) the reflected flux of one side leg reinforces the flux of the opposite leg. The secondary legs are in parallel with the primary leg but in series to each other current vise.

Consider the moment where the mmf of the primary (P) points up the flux also flows up (source) and divides equally to each of the secondaries (S1 and S2). With the winding direction shown the current enters the no dot end at the bottom (right hand rule). The generated current of the secondaries (when loaded) has their mmfs pointing up too to cancel the flux of the current from the primary (Lenz's law). The generated current in the secondaries has the current exit the no dot end to cancel the source flux of the primary winding (right hand rule). But as connected in series the current of one secondary enters the other secondary in the opposite direction to actually reinforce the flux of the opposite secondary. I.e. the opposite secondary sees the flux from the primary as well as the flux from its other secondary as being in phase. E.g. the Lenz generated flux of S1 flows up (its mmf points up) to tend to cancel the flux of the primary and then continues around the ring going down S2 (same direction as the flux from P). The same happens in the opposite direction from the other secondary S2.


The magnetic field moves at a finite speed slower in a magnetic core than through the air. My guess is that the waves making up the magnetic field which is coherent generated from the incredible number of charge carriers moving along the turns of a leg becomes coherent between the separate windings S1 and S2 sharing the same current. It's like LASER light. As the energy density is squared when the fields becomes coherent this could explain any excess energy or power output from the transformer.

One problem is that it is hard to tune the parameters for that OU effect. Any change in a parameter seems to make it go out of OU. I may have to redo my measurements with the bridged amplifier instead of the measurements done with the single ended amplifier. Distortion of the output signal by power supply pumping may cause the excess power output. At least this has to be known before making any claim valid. The problem is increasing input power to the amplifier when the reactive power to the transformer is increased. Reactive power should only take some initial amount of energy and enough real power to make up for any loss like resistance in the wires and connected components of the primary tank circuit and the amplifier itself.

 
Regards
Ole