diyAudio (http://www.diyaudio.com/forums/)
-   Everything Else (http://www.diyaudio.com/forums/everything-else/)
-   -   line frequency conversion (http://www.diyaudio.com/forums/everything-else/225782-line-frequency-conversion.html)

 gmaslin 15th December 2012 10:49 PM

line frequency conversion

I need to down convert a 1000Hz power signal to 60Hz with minimal power loss. Where should I be looking?

 freax 16th December 2012 03:18 AM

easiest would be conversion to dc then to 60hz by use of an inverter, what wattage, voltage and number of phases, and where the heck are you getting 1kHz power from?

Is Thomas Edison rolling in his grave again? :D

 Elvee 16th December 2012 08:01 AM

Quote:
 Originally Posted by gmaslin (http://www.diyaudio.com/forums/everything-else/225782-line-frequency-conversion-post3286625.html#post3286625) I need to down convert a 1000Hz power signal to 60Hz with minimal power loss. Where should I be looking?
A cycloconverter is what you need.
But operating at 1KHz means the usual solutions won't work, unless you use fast or GTO thyristors.

You could also make a cycloconverter from other active components, like IGBT's.

This would even give you more degrees of freedom, like making a full bilateral converter.

What kind of power level do you need?

 gmaslin 16th December 2012 11:38 AM

Thanks to all for the responses. I'm looking to re-purpose an electrical generator that outputs 5A three phase 500VAC @1kHz to 125VAC @60Hz. The obvious solution would be to add 16 poles to the generator but that route has practical challenges I would rather avoid so I am looking for an external solution.

 gmaslin 16th December 2012 12:27 PM

Ooops! I meant remove 16 poles not add.

 DF96 16th December 2012 12:55 PM

Railway traction sometimes has to solve similar problems, but at much greater power levels, so you might get some ideas there.

Basically, you need a high efficiency rectifier and a high-efficiency invertor. I am tempted to suggest Class E for both, but then I am biased.

 freax 16th December 2012 01:03 PM

you could say you're biased for Class-E

its a shame that you cannot rewind the generator section, or find a replacement for it that already has 115vAC/60Hz

 gmaslin 16th December 2012 05:43 PM

freax
If I did that, it wouldn't make the same power. The speed is making the power here.

DF96
I am assuming the generator is making AC so why would I want to rectify and invert? I believe Elvee pointed me in the right direction with his suggestion for the cycloconvertor. One can be build to reduce the waves to groups of 16 which should get me near my goal. I am concerned about electrically synchronizing those groups. How forgiving are consumer electronics to slight variances in cycles (ie: 5% over a 24 hour period)?

 DF96 16th December 2012 08:05 PM

Using DC separates the link between the two frequencies, which may or may not be what you want.

 freax 17th December 2012 06:12 AM

Quote:
 Originally Posted by gmaslin (http://www.diyaudio.com/forums/showthread.php?p=3287550#post3287550) freax If I did that, it wouldn't make the same power. The speed is making the power here.
And if you build a cycloconverter there is going to be a voltage drop and a certian amount of power dissipated into the diodes, and a limitation on the maximum wattage that you can pull through it before a diode goes pop.

By converting it to DC first you are then essentially creating an inverter generator, which produces some of the cleanest AC that you can get, if you buy a quality inverter that is.

I also hope someone else on here knows how to build a cycloconverter, properly, and I hope you do too, a lot of nasty mains wiring there by the looks of it.

Quote:
 DF96 I am assuming the generator is making AC so why would I want to rectify and invert? I believe Elvee pointed me in the right direction with his suggestion for the cycloconvertor. One can be build to reduce the waves to groups of 16 which should get me near my goal. I am concerned about electrically synchronizing those groups. How forgiving are consumer electronics to slight variances in cycles (ie: 5% over a 24 hour period)?
To turn that into dc so you can then convert the frequency to 60Hz you first must shed a few cycles.

Doing that with diodes means that they might end up needing to be matched sets of diodes, I think you should check this with the other guys here to see if it needs to be matched.

Make sure you do because if you dont then the diodes will blow as one or two of them draw too much current.

All times are GMT. The time now is 10:03 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.