In your estimate, how much leeway do you think we have in regards to the core specifications? Can you determine if there are certain characteristics that would clearly push a particular core outside of a tunable range via the electronic components?
I really do not know. I don't have sufficient information what is supposed to happen inside that Akula transformer.
Given a working transformer, I can tell you what's happening inside it, but
I cannot tell you what is supposed to happen unless I postulate some AdHoc operational principle ...or at least see a scopeshot of L2 current in a working device.
I don't want to postulate an operating principle without concrete data. All I can write to you is that Akula's circuit is not OU with a conventional "transformer" behaving in the usual manner.
Generally, an E-core can form a parallel magnetic circuit while an U-core can only form a series magnetic circuit, since the flux can take only one path through a U-core (besides leakage).
Thus those cores exhibit very different flux distributions and you cannot expect one shape to behave as the other,
Faraday's power transfer efficiency will be always lower in an E-core if only one leg has a secondary winding on it and another has a primary ...but a Faraday's power transfer in a transformer is a conventional effect ...not what we are after.
If you ever see any hints of that R5/R7 junction going below ground, even for a microsecond, that will be your sign of an anomaly.
The TL494 is wired to react to that, too...
Transformers are one of the most complex electronic components and worst of all, they are not standardized.
Anything can affect their operation, such as:
1) Core
a) AL value (material and gap dependent)
b) Shape and size
c) Conductivity
d) Air gap
e) Material in the air gap (e.g. hard mica or sound dampening paper)
f) Frequency response (mag.viscosity)
g) Coercivity
h) Hysteresis loss
i) Saturation value
j) Crossection
k) Permeability
l) Magnetostriction
m) Molecular configuration
n) Nuclear configuration
o) Villari permeabilty variability
p) Mechanical compression of the core (or
mechanical freedom to vibrate)
q) Any embedded permanent magnets
2) Placement and orientation of the windings in reference to:
a) the core (bobbin specs)
b) the air gap
c) the shield
d) other windings
3) Winding technique
a) single layer
b) multiple odd layers
c) multiple even layers
d) winding direction
e) winding pitch & advancement direction (can vary between layers)
f) spacing between turns
g) turn count
h) wire composition (most are copper but not all)
i) wire Litzing
j) filarity (e.g. bifilarity, aiding, opposing)
k) winding tightness/looseness/binding/gluing/varnishing
l) size of the windings (localized/narrow vs. widely spanning)
4) Isolation material
a) of the wire
b) between windings
c) between windings and core
d) between windings and shield
d) between layers
e) between core halves
5) Shield
a) material
b) size
c) shape
d) placement
e) connection
6) Pinout sides
7) External magnetic fields
8) External electric fields (see the IEEE article by Konrad & Brudny)
9) External vibrations (see
this video)
10) Core and Winding Temperature
So keep the list above in mind, next time somebody says or writes: "Just wind a transformer - all the turn counts are listed on the schematic..."
It would be irresponsible of me to guess and mislead you on any of these points listed above without being certain of the M.O.
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Topic: Akula0083 30 watt self running generator. (Read 975264 times)
