~20V AC threw ~100V AC to 12 V AC
 

So I am working on an interesting project, but not ready to say all the info on it yet. But I'm looking for an AC to AC step down converter that will take an input as low as 20 volts +/- 15 volts and as high as 100 volts +/- 15 volts but will have an output of 12 volt AC [an output of 12 volts DC will work too]. The current I would be working with is about 20 amps, but 10 amps will work too. An assembled product is preferred, but if there's only schematics that will be fine.

I just realized I said threw. I meant through*

SMPS. DC-DC converter,with an input range to cover your needs,and a (regulated?) 12V output.

20V with a tolerance of +/-15V? So,as low as 5V?
A supply with an input range of 5V-120V isn't going to be easy to find,or build.
It'll have to be some kind of buck-boost supply.

"The current I would be working with is about 20 amps, but 10 amps will work too."

Is that for the supply or the load?

DUG: that is for the load.
DigitalJunkie: I'm looking for anything with a range as large as 5V-120V or as small as 35V-85V, sorry I should have worded that better.

35V-85V would not be difficult. PWM step down.

5V-120V would be very complicated. Dynamic full range or static conditions?

I'm still not sure of what you really want.

35v-85v would be good enough. I would need it to be dynamic for the supply, and static for the load at 12v. Is there anything out there that is already near that range being sold, that would make things easier.

As DigitalJunkie posted in #3, rectify to DC and then used smps to down convert

Did a digi-key search and found 2 that would work (dc-dc), but of course neither are in stock.
FK1301-7R Power-One | FK1301-7R-ND | DigiKey
CK1301-7R Power-One | CK1301-7R-ND | DigiKey

only $5400 ea

Is that what you were looking for?

Well that is slightly pricy.. but I found this:
"Name: DC~DC Step Down Voltage Converter
Model: EZ-DCSD8012-20
Input Voltage: 30V ~ 80V DC
Idle Output Voltage: 14V ± 5% V DC
Load Output Voltage: 12V ± 0.5 V DC
Overvoltage Output Protection: 17 V DC
Rated Output Current: 20A
Rated Power: 240W"

It's $70

yea, cheaper when non-isolated

If that meets your need then that is great.

:)