I'm in the planning stages of building a custom pinball table and one of the sticking points is powering the flipper coils. They're 50V DC coils with a resistance of only 4 ohms during the stroke. That's 12.5 amps, and there are two of them so potentially up to 25 amps.
However, they are only high power for the length of the stroke, when an "end of stroke" switch uses the full coil resulting in 133 ohms resistance bringing it down to a much smaller 0.376 amps which is all it needs to hold the flippers up.
"Real" pinball machines use a massive transformer with a full bridge rectifier. They're unregulated (I believe), which is fine, and have several taps for other voltages I'm not concerned with generating (much easier ways). But I'm not having much luck finding something similar for the 48-50 volts that isn't several hundred bucks.
Trying to design something though I'm not sure what to aim for. The 12.5 amps (each) is for such a short duration it seems like overkill to design something that can handle that much power continuously. However, I don't know how a modern switching power supply would handle such an impulse. I feel like it would think there is a short circuit and shut down to protect itself.
I've heard of people using ATX power supplies from PC's, just daisy chaining 4 of them together to get the +12V rails up to 48V (which is close enough). These can be had for fairly cheap (~$15/ea) and have a lot of power (25+ amps).
How would these handle an impulse load like that? Can they be connected serially without other issues? Is there a simpler solution?