Silly question about voltage and current

[Farmhand]

I have a question: Do the voltage and the current for a cetrain load have to come from the same source?


Or could I, example given, use two independent sources like photopholtaic and wind or whatever, then go out of phase with each one by -90 resp. +90 degrees with a cap and a coil, then ac- sync this so in none of them is actally both (v+a) present, then simply but these together , maybe trough some diodes, to get a complete, working source of V+A ?

It works like this as I see it. If the two supplies are electrically isolated until the outputs are merged, then each circuit will take it's own return current only.

ie, The HV circuit supply voltage causes the HV circuit's current and so the current caused by the HV will return to the HV supply.
The LV supply circuit's voltage causes the low voltage circuits current and that current will return to the LV supply.
Now if the HV and LV output are simply superimposed and have common grounds the HV will see the LV as a load.  Like connecting the output of a flyback transformer to a battery. LV is load to HV.
If the reverse current is blocked to prevent that then the load determines what gets loaded the most.
If the load is high resistance the LV supply will do no work.

It's really quite simple and comes down to what pushes what, and current loops in separate supply's. It's not rocket surgery.

The voltage causes the current to flow in a (loop). Each supply will have it's own loop.

If we talk AC and we apply 10 000 volts positive half cycle to 150 volts negative half cycle, there will be a potential difference of 10150 volts, if the two circuit grounds are common the HV supply will see the LV as a load.

Cheers

EDIT: I talk in 'conventional' positive to negative current, not "electron current'. Flow of 'charge' (or whatever), not electron movement. Just to say how I think with respect to "current" flow.

It should be noted and logic that if the two were superimposed on the same conductors then the HV and the larger current will likely be measured, but they won't perform work together, the HV and it's associated current will do most of the work if the load is high enough resistance.

It basically conforms to work done at input and energy output. V x A only applies to the A caused by the V that caused it, and means power not energy anyway..

Spock and Kirk (Logic), Make up your own minds who is Spock and who is Kirk. 
http://www.youtube.com/watch?v=Kc6Vu-NLu0M
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If we add a Flea to an Elephant will we end up with a Flea the size of an elephant ( would be a nasty animal), or an elephant the size of a flea, or will we just end up with, a Flea and an Elephant ?

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[Farmhand]

This is kinda interesting and I think discussing it and thinking about it would help the less experienced to better visualize voltage and current.

IF we could post some drawings of situations where the mixing of HV-LC and LV-HC may be achieved then the circuits could be evaluated. And the effects seen in a picture.

The drawings would need both HV and LV supplies included with any groundings and the load/loads, supply - load isolation if any, ect. ect..

Pencil paper and eraser are cheap and work like a simulator to a degree, we just need to add the visualization based on what we know happens, though it can get complicated, it's often simple when seen on paper. I draw the supply itself then the circuit from positive to negative as much as is possible.

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[MarkE]

This is kinda interesting and I think discussing it and thinking about it would help the less experienced to better visualize voltage and current.

IF we could post some drawings of situations where the mixing of HV-LC and LV-HC may be achieved then the circuits could be evaluated. And the effects seen in a picture.

The drawings would need both HV and LV supplies included with any groundings and the load/loads, supply load isolation ect. ect..

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The relationships are not complicated.  Assign whatever voltage you like to each of the two sources.  Assign the corresponding internal resistance values.  The problem that you will run into is where the current limit of the high voltage supply causes the value of the associated resistor to be variable, and the resulting external voltage across the combination of Vx and Rvx to collapse.   

[Farmhand]

But Mark those supplies are in series. I'm not sure that is what is meant by the original poster.

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[MarkE]

But Mark those supplies are in series. I'm not sure that is what is meant by the original poster.

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If you want the voltage of two supplies then you have to put them in series, and the loop current will be limited by the supply with the lower current limit.  A 25kV 1mA supply in series with a 2V 150A welder will still only deliver 1mA.  If you want the current of two supplies then you connect them in parallel, and you will be limited by the lower voltage of the two.