Uncle Peter wrote:
Guys,

How do the "new" inverter technology microwave ovens operate?

Pete

They work in a manner that is very similar to the way the old
60Hz transformer style ovens operate.

They convert the mains AC to DC using a voltage doubler (US),
and convert the DC into a 100KHz square wave that feeds a small
ferrite cored transformer that contains a HV winding, and a
filament winding.

"Power" is controlled by cycling the oven on and off over a
10 second cycle: 10% = 1 second on, 9 seconds off, 20% = 2 seconds
on, 8 seconds off, ...

-Chuck