As I have all the bits available as surplus junk on the shelves,
thought I would put together a QRO class-E PA based around Alan's
spreadsheet, (with mod for matching built in).
But before comitting to any particular power level / supply
voltgage combination thought I'd ask what others have reliably achieved
with a similar setup.
Starting parameters :
Supply voltage anything from 28 - 55V adjustable. 25 A max
PA device - IRFP452 (have a small handful, so can allow a
few to go pop) Rated 500V, 0.4 Rdson, 14A, 190 Watts
Drive, accurate 50% square wave from ICL7667
Resonant Inductor - air wound with 2mm Litz wire.
I reckon that at 55V 500 Watts might be a value to aim for with
a single device, with the option to back off by lowering Vsupply.
But before committing to winding inductors and making parallel
combination of high voltage caps, does anyone have any practical
experience? Am I aiming for too high a power perhaps.
No, 500W by one of these FETs at 500 kHz should be possible, although
the efficiency will probably be 85 to 90%. But if you have a 55V/25A
supply, why don't you develop a 1 kW PA? If it is designed to give 1 kW
at 50V, you'll get a good 50W at a car battery so it is even usable in
/p or /m :-)