While cleaning up my mail box I stumbled upon this link:
http://www.historical.hilo90mhz.com/electronics/inverter/inverter2.htm
which is about a fixed-frequency 15 kW 3-phase inverter. Looks like an interesting project, so have a look.
BTW, we are progressing with our variable frequency 3-phase inverter, soon we will be trying out our prototype. Crash 'n' burn :-).
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