Re: Higher Mains Frequency

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, June 19, 2003 8:34 PM
Subject: RE: Higher Mains Frequency


 > Original poster: "Black Moon by way of Terry Fritz <teslalist-at-qwest-dot-net>"
<black_moons-at-hotmail-dot-com>
 >
 > Very intresting... I thought at 400hz there would be much less inductive
 > current and therefor not to much eddy current but I guess I was wrong
 >

Eddy current losses are largely determined by the thickness of the
laminations.  Thinner for higher frequency.  Since a big factor in the cost
in making transformers is in stamping out the laminations, not the raw
material (steel) mass, they design the laminations as thick as they can be
for acceptable "iron losses".  Steels with very high resistivity are also
used; the material is more expensive, but because it's high resistivity, you
can use thick laminations, which means you need fewer of them for a given
core cross section.  Taken to an extreme you have powdered iron (powdered
metal) or ferrite cores, as for RF.