I have real 2 phase high voltage (two of 3 legs from the power substation). (The Two phase high voltage was used here when this place had a Sawmill on the site. Three phase is on both sides of the highway with local poles for houses. My trunk off the main line is 1400' long. I had 1600' but lost 200 in a bad storm and a tree fall.)
I have only single phase 240 in the shop. I spin up 3 phase in a rotary and drive six transformers. Six ? - yes three large voltage step up transformers with boost transformers on each output.
It has been working just fine. The core of the transformer absorbs energy from voltages / currents dumped to it in the primary or secondary.
Since it goes into the core, it can come back out. When the tool goes below that voltage / current value the transformer magnetic field will start to collapse and will generate voltage / current as it needs.
Just like the motors do when they come under load and the load eases off. Under load it draws more current to keep on going when the load slacks off the magnetic field in the core begins to collapse and generates the voltage/current.
Mart> >