AC-AC Voltage Regulator

[PFITZ]

Hi,

Just wanted to bounce a quick question out there as I don't have much
experience in this field, but Is there a device that exists that will
regulate an AC supply to a certain Voltage? I'm looking at
incorporating this stage in a design at present.

What I'm looking at currently needs to be only step-down. But if there
are Buck-Boost types that would do also.

Ideally I'd like to build something discretely to do this job, I want
to regulate 50Hz ~240VAC down to 50Hz 180VAC.

A trasnformer won't work because the input will see variations and I
don't want these present on the output.

If anyone can point me in the right direction, I'd be much obliged.

P

 

[PFITZ]

Hi,

Just wanted to bounce a quick question out there as I don't have much
experience in this field, but Is there a device that exists that will
regulate an AC supply to a certain Voltage? I'm looking at
incorporating this stage in a design at present.

What I'm looking at currently needs to be only step-down. But if there
are Buck-Boost types that would do also.

Ideally I'd like to build something discretely to do this job, I want
to regulate 50Hz ~240VAC down to 50Hz 180VAC.

A trasnformer won't work because the input will see variations and I
don't want these present on the output.

If anyone can point me in the right direction, I'd be much obliged.

P

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

 

[Jan Panteltje]

Hi,

Just wanted to bounce a quick question out there as I don't have much
experience in this field, but Is there a device that exists that will
regulate an AC supply to a certain Voltage? I'm looking at
incorporating this stage in a design at present.

What I'm looking at currently needs to be only step-down. But if there
are Buck-Boost types that would do also.

Ideally I'd like to build something discretely to do this job, I want
to regulate 50Hz ~240VAC down to 50Hz 180VAC.

A trasnformer won't work because the input will see variations and I
don't want these present on the output.

If anyone can point me in the right direction, I'd be much obliged.

P

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:
http://en.wikipedia.org/wiki/Voltage_regulator

 

[Martin Griffith]

Hi,

Just wanted to bounce a quick question out there as I don't have much
experience in this field, but Is there a device that exists that will
regulate an AC supply to a certain Voltage? I'm looking at
incorporating this stage in a design at present.

What I'm looking at currently needs to be only step-down. But if there
are Buck-Boost types that would do also.

Ideally I'd like to build something discretely to do this job, I want
to regulate 50Hz ~240VAC down to 50Hz 180VAC.

A trasnformer won't work because the input will see variations and I
don't want these present on the output.

If anyone can point me in the right direction, I'd be much obliged.

P

http://www.watfordcontrol.co.uk/prod_rotavolt.asp


martin

 

[Phil Allison]

"PFITZ"

Ideally I'd like to build something discretely to do this job, I want
to regulate 50Hz ~240VAC down to 50Hz 180VAC.

A trasnformer won't work because the input will see variations and I
don't want these present on the output.

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

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

And regulated.

Keep dreaming.



...... Phil

 

[PFITZ]

"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?

 

[Glen Walpert]

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

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.

 

[Phil Allison]

"PFITZ"...

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

And regulated.

Keep dreaming.

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............. . ................... ......................

**** off you pathetic bloody TROLL.

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



... .. Phil

 

[MooseFET]

Hi,

Just wanted to bounce a quick question out there as I don't have much
experience in this field, but Is there a device that exists that will
regulate an AC supply to a certain Voltage? I'm looking at
incorporating this stage in a design at present.

What I'm looking at currently needs to be only step-down. But if there
are Buck-Boost types that would do also.

Ideally I'd like to build something discretely to do this job, I want
to regulate 50Hz ~240VAC down to 50Hz 180VAC.

A trasnformer won't work because the input will see variations and I
don't want these present on the output.

If anyone can point me in the right direction, I'd be much obliged.

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.

 

[Paul E. Schoen]

"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?

=========================================================================

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

 

[Paul E. Schoen]

"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?

============================================================================

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

 

[Rich Grise]

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.

http://www.solaheviduty.com/products/powerconditioning/Index.htm

Cheers!
Rich

 

[[email protected]]

Hi,

Just wanted to bounce a quick question out there as I don't have much
experience in this field, but Is there a device that exists that will
regulate an AC supply to a certain Voltage? I'm looking at
incorporating this stage in a design at present.

What I'm looking at currently needs to be only step-down. But if there
are Buck-Boost types that would do also.

Ideally I'd like to build something discretely to do this job, I want
to regulate 50Hz ~240VAC down to 50Hz 180VAC.

A trasnformer won't work because the input will see variations and I
don't want these present on the output.

If anyone can point me in the right direction, I'd be much obliged.

P

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.

 

[PFITZ]

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.:
‘Design of a novel ac
regulator’, IEEE Trans. Ind. Electron., 1991, 38, (2), pp. 89–94" 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