[Power] Haiti power questions

[forster at ozonline.com.au]

> That sounds like a good first step.  That gives you the data and 
> questions that you can ask or look for in the specifications.   How does 
> that scale when you have 100 XO's on the wire?
> 

I have measured the current.
http://wiki.laptop.org/go/Plug_packs

The harmonics are really bad, I can see them causing problems when there are a lot of chargers and no other load.

The issue of capacitors is complex. Power factor correction capacitors won't help much because it is not a lagging (inductive) power factor. Capacitors might soak up some of the harmonics but only to the extent that the supply is inductive, they would have no effect on a perfect voltage source, the perfect voltage would still have imperfect current, the problem still there. In the real world case, the capacitors would be able to absorb harmonic currents because of the supply inductance. The capacitors would also form a series tuned circuit with the supply inductance and the voltage could rise, possibly dangerously. To soak up harmonic current, the capacitance would need to be significant wrt supply inductance meaning also significant resonance. So connect capacitors with care.

100 chargers is roughly 100 times the current but there is some timing misalignment, at least between brands, so the pulse broadens a little.

12V DC is looking good

Tony