Originally posted by nilrehob
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http://www.energeticforum.com/renewa...inductors.html
Also see: Capacitors - Multiple Capacitors
So, the energy contained in two capacitors switched in series vs. parallel is the same, given a certain charge VOLTAGE:
Parrallel: Vp = V0, Cp = 2C:
Ep = 1/2 * Cp * Vp = 1/2 * 2C * V0 = C * V0
Series: Vs = 2 V0, Cs = 1/2 C:
Es = 1/2 * Cs * Vs = 1/2 * 1/4 C * 2 V0 = C * V0
We still have the same energy. Ok, so far, so good.
Now let's look at the CHARGE Q:
Parrallel: Vp = V0, Cp = 2C:
Qp = Cp * Vp = V0 * 2C = 2 C V0
Series: Vs = 2 V0, Cp = 1/2 C:
Qs = Cs * Vs = 2 V0 * 1/2 C = C V0
Yikes!
HALF THE CHARGE IS LOST!
Gone up into thin air!
This can probably be explained by that the charge on the negative plate of the top capacitor and that on the postive plate on the lower capacitor cancel each other out.
Now this is very interesting, if you want to charge capacitors from a current source (such as an inductor.... ):
If you put a certain charge Q (fixed current) into two capacitors switched in series vs. parallel, you get:
Parrallel: Qp = Q, Cp = 2C:
Vp = Qp / Cp = Q / 2C = 1/2 Q/C
Series: Qs = Q, Cs = 1/2C:
Vs = Qs / Cs = Q / (1/2 C) = 2 Q/C
In other words: you get 4 times as much energy for the same amount of charge fed into two capacitors if you charge them in series rather than in parallel!!!
So, if radiant spikes are to be considered as "current sources", which I think they do, it would be a good idea to capture these spikes using capacitors in series, rather than using single capacitors or caps switched in parallel.....
Note: if you take 4 caps in series and charge them from a current source, you'll even get 16 times as much energy for the same charge buck.....
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