🚀 go-pugleaf

In sci.electronics, mathiega@elec.canterbury.ac.nz (Grant A. Mathieson) writes:

> Since reading a paper...

> "Class-E Resonant Regulated DC/DC Power Converters: 
> Analysis of Operation, and Experimental Results at 1.5 MHz"
> Redl, R., Molnar, B., and Sokal, N.O., IEEE Power Electronics 
> Specialists Conference 1983

> ...I have developed an interest in Class-E techniques for 
> Power Conversion, which mimic those used in Class-E RF 
> Power Amplifiers. 

This is something I have wondered about for a long time, since
first reading about "Class E" some 20 years ago.  It seems to
be a solution looking for a problem to solve.  Now that Mr.
Sokol's patent on it is about to expire, I imagine he has
gone on to other things.  As near as I can tell, "Class E" is
basically just a resonant switching technique, of which there
must be a half dozen basic types in use today.  The difference 
is that Class E runs at a constant frequency, whereas the
resonant techniques now popular with power supply vendors such 
as Vicor use variable frequencies.  The variable frequency allows
the supply to do line and load regulation.  Most of the class 
E circuits I have seen are unregulated.  I don't know what 
Sokol does in the above paper to get regulation.

Kind of reminds me of Mr. Cuk and his "Cuk converter" whose
patent will also expire soon.

Then there is "integrated magnetics".

What they all have in common is a lot more papers written about
them than actual designs utilizing them.  

Rick Karlquist
rkarlqu@scd.hp.com