Question the first: where to find transformer (or inductor) cores? Mouser and Digikey don't sell them plain. Who's the magnetic equivalent of Digikey?
Other question: how to select cores? Specifically, I'm looking for something in the 10kHz (square wave, PWM), 10kVA range, with high permeability to minimize the number of turns. Saturation should be fairly high, given the low operating frequency. Ratio 4:1, with about
200Vrms (fundamental component) primary and 50Vrms secondary. The secondary will be copper tubing, 1/4 or 3/8" dia., so a one-turn secondary is advantageous.Given the permeability and saturation, I'm thinking something like Metglas. I know I need something in the 2-3" range, and I can calculate things like A_L and A*t(sat) from the properties, but it would be a whole lot easier if I had both parameters laid out in a table of standard shapes. I can't really make any estimates on what size I need if I don't have a standard formula for the geometry, so I don't even know what inductance and magnetizing current and saturation I have to look for.
And why do they never specify amp-turns saturation? It's always in B. I can measure amp turns, I can't measure Teslas. They give A_L by the core, but not saturation, what the hell?
Tim