Randy Gross said:
Can someone steer me to a page that explains magnetic shunts as applied to
transformer current limiting. I'm coming up negative with the search
engines.
Suggest you use other sources than the web, if you want something more
than basic transformer theory. If you're looking for exercises and
examples, a text book for electrical engineering is probably the
closest thing you'll find - 60Hz transformer design does not seem to
have caught fire in the public imagination, at least not in the short
history of the internet.
In the welding industry you may see them called fixed-current
transformers, but in general design they are simply loosly coupled (or
variable reluctance for adjustable coupling) transformers. The
configuration is also used commercially for lamp ballasts and (as you
know) microwave heaters.
You don't need a shunt to get the effect - it's used to get the same
effect in a smaller device.
They follow all standard transformer design rules, but are obviously
material and labour critical in a 60Hz commercial application. This
will generate odd design rules that don't belong in any text book,
being the result of application-specific mechanical iteration.
.....................
"Investigation on the Topological Configuration of Magnetic Current
Limiter for the Protection of Power Semiconductor Devices"
S.C. Mukhopadhyay, F. P, Dawson, M.lwahara and S.Yamada
IAS2000
http://manuales.elo.utfsm.cl/conferences/seminarios/Eenergy/DATA/55_06.PDF
RL