| Another advantage of 400 Hz or 60 Hz is that the minimum speed of a 2
| pole/phase alternator is 3600 rpm with 60Hz but 24,000 rpm at 400Hz. 3600
| rpm is a little on the slow side.
Did you mean "or" in "400 Hz or 60 Hz" or did you mean "over"?
Why is that minimum speed relevant, given that a multi-pole/phase alternator
could be used instead?
However, 3600 rpm for 60 Hz and 24000 rpm for 400 Hz do represent maximum
speeds for syncronous motors, or near those speeds for induction motors.
So 400 Hz has an advantage. It can be made for up to 24000 rpm or any
lesser speed in multi-pole versions. There I do see an advantage of 400 Hz.
I'm curious how hard it might be to make a computer PSU that would run on
any frequency from 50 Hz to 400 Hz (or maybe wider), compared to just the
50 Hz to 60 Hz range.
|> I am not really up to date on radar power supplies. I would expect that
|> high power radar power supplies would be more advance than using dc and
|> conversion. The same solid state technology that makes dc to dc
|> conversion easy can also be used to rectify ac for feeding into dc to dc
|> converters. After all, a three phase bridge rectifier is easily
|> implemented and starts with relatively low ripple.
| Yep! At higher frequencies I don't thing it's important to have 3 phases
| available. Phase shifting caps, if needed, are a franction of the size
| needed at 60hz.
And in other cases a motor controller can be used (brushless DC motor).
So if they don't have a need for three phase, but do have a need for 60 Hz
power on board (ship or aircraft, but consider each might have a different
answer to this), what voltage(s) would be available? I would consider that
at least for military purposes, they would want to have the ability to run
anything they might get their hands on during "missions", and so they might
want to be sure they have all common world voltages, or close to them, if
not also frequencies. 120, 208, 240, 277, 416, 480?
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