Re: [ATM] synchronous motor and cheap inverter - tests and question.

["Bob May" <rmay@nethere.com>]

The Willmann-Bell convertor used the old technology of driving a
regular transformer backwards (quite legal to do!) with a pair of
transistors directly off of the 12V input power.  This means that
you have a big heavy transformer to hold things down.  The
commercial convertors long ago gave up that idea and no convert
the 12V directly through a DC-DC convertor to about 200VDC which
is then run through a H bridge circuit and thence out to the
output plug.  The transformer for the DC-DC conversion is tiny by
comparison to the older 50Hz transformer and thus is a lot
lighter and due to its construction design is a lot cheaper to
build.  More parts but they are a lot cheaper than the big
transformer in the old design.
Bob May

rmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net


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