Re: SS MOT's ----> possible mod's for TC Power

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

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

>
> > I just read an aritcle in the current
> > edition of new scientist that samusung are
> > planning to make toaster sized microwave
> > ovens using switch mode power supplies -
> > these are apperently 95% lighter and 75%
> > smaller than a standard MOT. It'll be
> > pretty cool when they start showing in
> > scrap yards, imagine - 2kw coil that only
> > weighs a few Kg's.
>
> Panasonic has already done it to some degree...but not to the spec's
> you quote I don't think. To me it seems unreasonable that you could
> stuff 600W at 2.5kV into a package 75% smaller than a 4" x 4" x 4"
> MOT. But SMPS technology is getting AWESOME nowadays, so maybe so.
> Power density keeps going up and up...and weight/size is going down
> and down. I think eventually, like everything else, there will be a
> limit but I don't see it stopping soon. It all depends on the quality
> of the semiconductor used...but I digress, so anyway.


Efficiency of >95% is entirely possible for a SMPS, especially one in a
microwave oven that has essentially constant load.  This would mean that the
"cube" would dissipate only 30 Watts or so (for a 600 W load).  As for
physical size.. A lot is determined by the HV insulation and thermal
dissipation requirements.  600W in a 4x4x4 cube would be easy.  Off hand,
4x4x1 isn't out of the question, but, remember that consumer equipment gets
designed in incremental changes.. There is a lot of other bulky stuff in a
microwave oven (like the magnetron), so chopping a few cubic inches out of
the power supply isn't going to help a lot, since the overall package is
still going to be a "box".  I suspect the first thrust will be to reduce
cost.  iron and copper are expensive.