Don Merz 070317 posted:Adrian and GRJ--thanks for the answers and the great thread. I am such a nerd that I think this is a FUN DISCUSSION! Hah.
Rattling around in my brain is the issue of the train motors. Doesn't the electricity see the motors as inductive?
Don Merz
It's a good question but pretty complicated to answer. The hand-wavy answer is the PS2/3 board in the engine takes up the AC, converts it to DC, then applies pulse modulation. The impedance seen looking into the engine is referred through the conversion electronics (which has a big ripple-removing capacitor inside). As a result the natural V to I phase relation of the motor is broken and the load doesn't look inductive.
Also in front of all that conversion there is a choke of a few uH keeping the DCS from flowing into the power electronics in the first place.
