AC-AC Voltage Regulator

Just to also add, I would need it to be capable of supplying >50A.

On a sunny day (Wed, 30 Apr 2008 01:49:59 -0700 (PDT)) it happened PFITZ wrote in :

There are AC stabilisers that use a resonant system, I think 1% is achievable. Cannot remember what those were called. No electronics is those. Oh, found it again: ferroresonant transformer This wikipdia link explains some of it:

martin

Just to also add, I would need it to be capable of supplying >50A.

Magnetic amplifiers? Saturable Reactors? come to mind as possible solutions. Might want to explore these. Daniel Thomas

"PFITZ"

** So you want greater than 9,000 watts from a 240 volt power outlet.

And regulated.

Keep dreaming.

..... Phil

Not continuously, the proposed product would be installed at the meter point, ie entry point to a house or apartment for the power. Is this completely impossible?

At your 9 kW power requirements you could use a custom constant voltage transformer, if you can find someone who still makes them, or a custom automatic tap switching transformer if you can stand the steps, or a motor generator set, or an adapted motor inverter with the optional output filter if what you want is three phase, or a custom inverter designed for your application.

But I suggest you start by determining how much line voltage and load current variation you need to deal with, how much output voltage variation you can stand (none is not a reasonable answer), and how faxt it needs to respond to line and load transients.

"PFITZ"...

Not continuously, the proposed product would be installed at the meter point, ie entry point to a house or apartment for the power. Is this completely impossible?

** Yawn............. . ................... ......................

Fuck off you pathetic bloody TROLL.

Phutttttttttt.............

.. .. Phil

If the variation is slow, there is an electromechanical solution. They make them but I'm not sure where you can buy them. I will attempt to explain how they work:

Imagine a 2 phase induction motor with a wound rotor. Imagine that one phase of the stator windings is connected to the incoming mains supply. Imagine that the other stator winding is shorted.

Now imagine that the rotor winding is in series with the power going to the load and that you have some sort of handle that lets you turn the rotor. When you point the rotor one way it will add to the mains voltage. When you point it the other it will subtract. As you turn it, the voltage will vary smoothly between the two extremes.

Now imagine that there are spings forcing the rotor to point in the direction that reduces the voltage and a solenoid that would pull it the other way when energized. We also need to add an dashpot (mechanical drag) to slow the motion of the rotor. Now imagine a circuit that energizes the solenoid any time the output voltage falls too low.

Not continuously, the proposed product would be installed at the meter point, ie entry point to a house or apartment for the power. Is this completely impossible?

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A motorized variac or Powerstat and a controller will do the job if slow response is OK. It is a good solution where waveform and efficiency are importsnt.

You can use a buck transformer with a 60 volt secondary to drop the voltage to 180 VAC, and it would only need to be rated 60 * 50 = 3000 VA. Its primary could be driven by a 3 kVA Powerstat, 240 VAC at 15 amps. Superior

246 or Staco 2520 would work. Look on eBay for surplus or some cheaper Chinese versions. You can rig a motor and limit switches to drive it. The motorized versions are expensive.

Paul

Not continuously, the proposed product would be installed at the meter point, ie entry point to a house or apartment for the power. Is this completely impossible?

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You might also be able to use a solid state motor controller. You would probably need to tweak the settings a bit to get 180 VAC at 50 Hz, but it will provide good regulation. If you build your own, you could synchronize the phase and frequency with the incoming line, if anything on the load side requires that (such as electric clocks). For 9 kVA, a 15 HP controller will do the job, but it's hard to find a single phase model at that power level. It would need a hefty capacitor bank. But you could add a battery pack, and your product would also provide brownout protection and would essentially be a UPS.

Paul

Cheers! Rich

A constant voltage transformer would do it, snag is they are expensive and unlikely to be the voltage you need so you would need a second transformer. You could possibly use an industrial inverter with a filter but that wouldn't be cheap either and would raise other issues.

Thanks for all the suggestions guys, especially that glorious insight from Phil.

I've done a bit of research and was wondering why something like the regulator described in "Lee, Y.S., Chen, D.K.W., and Cheng, Y.C.: =91Design of a novel ac regulator=92, IEEE Trans. Ind. Electron., 1991, 38, (2), pp. 89=9694" has not made it into mainstream production.

(maybe it has and I just haven't come accross one)

I'm going to do a little playing around and try to simulate some circuits and see what I can come up with before progressing. I'll let you guys know how I fare. Thanks again,

Rgds,

P