How to clean our ac power??

[peranders]

Jack, DC on the mains is very little and will only cause hard humming from time to time and it will not heat up any transformers, harmless in other words. Put a hair drier on half speed (half wave rectification) and you will get unsymmetrical AC => AC+DC

[Brett]

Originally posted by jackinnj
there's a tradeoff between the leakage inductance which mitigates spikes and the capacitance between primary and secondary which likes to pass them along.

I'm aware, but my comments are based on having done it and measured the difference in an RF lab that had some serious mains issues. Still a cheap solution as they usually go for not a lot of money.

[cocolino]

originally posted by Eva
Common mode signals appear between both phase and neutral, and earth, and they are easily radiated by wiring. Therefore, even an isolation transformer won't filter them at all due to inter-winding capacitance, but a common mode choke will do a great job.

And what about those socalled "Ultra-Isolator noise suppressor" transformers?
This are (mostly huge) EI Isolation-Transformers with a very special shielding technique.
According the datasheet their interwinding capacitance is as low as 0,005pf and smaller (yes, I got that right, "pf").

[sam9]

eeka chu wrote:

Could you not get a very clean mains electromechanically?

Eeka,

A dacade or so ago I worked for a company that did a lot of high power microwave stuff. The built a regenation facility for exactly the reason you hypothesize. Some of their R&D and test activities needed a super clean power source -- what's the point of building a $1M+ Faraday room and bring noise on you AC power??

[mzzj]

Originally posted by sam9
eeka chu wrote:


Eeka,

A dacade or so ago I worked for a company that did a lot of high power microwave stuff. The built a regenation facility for exactly the reason you hypothesize. Some of their R&D and test activities needed a super clean power source -- what's the point of building a $1M+ Faraday room and bring noise on you AC power??

I have read about similar project somewhere here, power was transmitted by 2 meters long glass-fibre axle trough emi shieldings.

[eeka chu]

Quite!

There's a million and one ways you could implement the idea if you start thinking about it. Anything that comes to hand.

How about each motor having a prop to drive a current of water around a toroidal channel?

I think it's kind of nice since you can usually score perfectly fine motors from things people are getting rid of just to replace with a newer version.

If you're moderately able with your hands it shouldn't be too hard to couple the two.

Or you could use a few motors in parallel to bump up the power rating.

You could put them in one compact housing in your garage provided you, like you've said mzzj, put something magnetically conductive between them. A piece of steel plate off cut would work I guess; ~5mm+ thick.

Of coarse, the windings would have to be hand wound from atomically pure silver by 18 year old virgin girls for true quality, but that almost goes without saying.

At least with the motor to motor idea you don't have to worry about recharging, charge lifetime, cell lifetime, chemical leakage, electrolyte replacement, lead disposal, unavoidably high cost, massive weight, large amount of space wasted and on and on...

[sam9]

Check out this URL:

http://www.geocities.com/water_trans...ansformer.html

[darkfenriz]

aside from filtering, simple metal-oxide varistor to limit voltage may be usable

[Livino]

To get a clean mains supply you might want to try an isolator module.

I have very "dirty" mains in my building and this thing's been providing a very clean supply. Mind you, there are only 440VA and 1kVA models.