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Convert Alternating DC to AC

Convert Alternating DC to AC

Convert Alternating DC to AC

(OP)
Hey everyone, I have a quick question.

I have an un-rectified alternating DC signal, that I'd like to convert to true AC.

Does anyone have any information on going about this process?

Currently, I alternate between +2 and 0, and I'd like to alternate between +1 and -1 (see attachment)

Any info would be fantastic.

RE: Convert Alternating DC to AC

Put a capacitor in series with the signal lead. If you want to be really fancy you can feed that into a non-inverting op-amp stage where you can adjust gain and it also acts as a buffer.  

RE: Convert Alternating DC to AC

(OP)
So a capacitor in series with the output will do what I want?

In practice, we will be working with ~12 to 20 volts, and around 5 to 10 amps...

RE: Convert Alternating DC to AC

Five to ten amps? You will nedd a lot of capacitors then. Hardly practical to do.

It would be very good if posters included the specs from the beginning. Specs and use. Not easy to answer a question without that basic information.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Convert Alternating DC to AC

It requires an external power source, but you could wire an adjustable DC power supply with isolated output in series with the signal to cancel the DC component, leaving only the AC component.

The DC power supply needs current output rating of at least 10A and voltage output rated for cancelling the maximum DC offset you encounter.

Another solution may be to remove the DC component at the source, perhaps the generator's AC output is being referenced to positive leg of battery or other DC supply instead of 0V?

Good Luck,
Sean

RE: Convert Alternating DC to AC

Yeah, a capacitor will still work. It probably has to feed the input of some type of linear amplifier (think audio amplifier) to get that kind of current.

Is this "generator" capable of sourcing the 5A to 10A the load requires? If so, the best bet would be to re-configure it to provide the AC output directly.

When you ask a vague question you get vague answers.

Funny how not only the current was missing from the question but now the voltage requirements have changed as well.

 

RE: Convert Alternating DC to AC

How about a 1;1 transformer rated for a voltage above your RMS peak?  

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Convert Alternating DC to AC

A transformer isn't going to very happy with a DC current. It might work, but heat and saturation could be issues.  

RE: Convert Alternating DC to AC

Air-gapped transformer might be ok though.
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

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