Hi hanon,
thanks for your answers to my questions.
Here is my thinking on the topics "Faraday's Law" and "50/60 Hz":
In order to exploit the aspect of Faraday's law that x-times the frequency (turning the Figuera-commutator faster) will lead to x-times the output, Figuera had to overcome a problem:
...High frequency is said to heat up the Iron core ...
That is correct
...so the core will have to be much bigger than at lower Hertz.
That is not the solution because with a bigger core more input-power is needed to magnetize it and so one meets the same problem again.
So theoretically it should be possible to get more output by raising the frequency but there is this practical problem. To find a solution let's look at one single cycle, when a single inductor gets energized by a single inducer:
The iron core gets magnetically polarized while the voltage in the primary rises.
The core gets magnetized.
Let's call this the first half of a cycle.
During the second half-cycle, electrical power will be created in the secondary. while the magnetization of the iron core subsides. At the same time, the voltage in the primary returns to zero.
This is true regardless of whether the primary is energized with a half wave of AC or a pulse of DC.
The faster you repeat this, the more output you will get in accordance with Faraday's law.
But once you reach frequencies above 60 Hz the output does not continue to rise. You meet a kind of barrier. The core heats up. Why?
Well, because it takes time for the core to de-magnetize (while the voltage in the primary returns to zero and the voltage in the secondary rises). If you hit the core with the next pulse of energy before the magnetization of the previous cycle has decayed - creating output in the secondary - the energy of all subsequent pulses accumulates in the coil creating heat and no electrical output.
The natural amount of time this demagnetization requires, is an inherent characteristic of iron. Scientifically it is expressed as "Hysteresis".
I think Figuera discovered a trick, that made it possible for him to raise the frequency and get around the mentioned limitation of the iron core.
He supplied a higher frequency than 50 Hz.
But not to one single set of primary and secondary. Instead he used several sets and divided the high frequency among them in such a way, that each set was running at 50 Hz.
He used his commutator two-fold: To create the frequency from a source of DC (Battery) and it also served as a distributor, i.e. as a frequency divider. Like a distributor of a petrol engine.
An example for the principle: If his commutator would be capable of supplying 400 Hz he would use eight sets. So each one would run at circa 50 Hz.
PS I have not built this. It just occurred to me following various postings of this forum.