Hello everyone, as I comment in another post I will try to give my point of view to the
devices that work sparkgap, it should be noted that I have not done tests
of any kind about these devices, I only apply the theory of how they could
operate them using electromagnetism.
First we define what is an inductor, although a common transformer has
primary and secondary inductance, is not the same.
We all know that transformers obey long-defined rules
time, as the tensions are proportional to the ratio of turns, that the current is inversely proportional to the relations of turns, things of those.
But they are really just impedance couplers.
The reflected resistance of the secondary to the primary is Rl' and its value is SQR (Np / Ns) Rl.
It should be noted that always in a direct sense, the energy passes from the source to the load
during the magnetization cycle through magnetic induction.
Now, flyback topologies do not work in direct mode, because
there is no current reflected to the primary during the magnetization cycle.
The magnetizing current stores energy equal to the square of the current
for the inductance divided by two, this is E = (Ipk ^ 2Lp) / 2.
Imagine a primary of 10 turns and secondary of only 1, let's see what happens ...
Suppose we apply a voltage and time of Ton in such a way that the current remains at 1A.
It turns out that the secondary current will be 10A, no matter the load!
Since the inductors operate in current, this indicates that 1A * 10Tp = 10A and this
Current ratio should remain constant at all times.
Well and the question that follows ...
What happens with the voltage on the secondary side?
This will obey Ohm's law in every rule.
If we put a load of 1 Ohm on the secondary the voltage will be 10V, if the load is 10 Ohm
the voltage will be 100V and with 100 Ohm of 1000V.
But we can not forget that the output voltage is reflected to the primary in Vds = Vs * (Np / Ns) + Vdc
due to live magnetic induction.
Let's see what happens according to the applied load ...
For the first case, load of 1Ohm, the voltage that would have to support the switch would be
100V plus the voltage that feeds it, in the second case it will be 1000V plus the supply voltage and in the third case of 10000V plus the supply voltage !!!
There is no current technology in the power switches that support such voltages.
But if a Sparkgap.
The previous case would be for the transformer with air core that forms the receiver device within the global circuit that composes it.
What does this mean…
If you look at the devices, they use a transmitter coil and a receiver, the first
in step-up and the second in step-down, but always through sparkgaps.
In the transmitter, a capacitor is charged at such a voltage that just when the medium is ionized
content between the electrodes sparkgap this causes a spark gap that in turn energizes the primary winding of few turns.
The current flowing through said primary is high and short time due to the low primary inductance.
On the secondary side of the same transformer to have a very low ratio (Np / Ns) the current will be reduced in the reciprocal of its ratio of turns 1 / (Np / Ns), but as the impedance of the medium that communicates said secondary with the primary of the receiver is high (another sparkgap), the voltage between the electrodes will be very high, this will reflect a voltage on the primary side extremely high, voltage that the sparkgap can support on the primary side perfectly.
From this study it is deduced that the instantaneous power transmitted from one point to another is high,
(between the two transformers to air core).
Only by adjusting the load value of the receiver side, number of turns of the transformers and looking for the auto-resonant frequency of the two transformers to be the same could be seen
if there really is gain in the system that involves it.
It is essential that the volt-seconds ratio be asymmetric, this is achieved if the system
works in resonant mode, the inductors should remain linear all the time, that's why
they are built to air core, since the permeability of the vacuum is constant.
I think it is the best approach to which these devices could work.
It would be necessary to physically prove the exposed thing here and to verify its operation.