Hi Mike
On (19 Nov 97) MIKE ROSS wrote to Alec Cameron...
 MR> I think the math to find the optimum load would look like this:
 MR>                           /--------------------------
 MR> Rload = E^2   - Rs +/-   / (E^2/Po - 2Rs)^2 - 4Rs^2
 MR>        ------           / ---------------------------
 MR>         2xPo          \/               2
 MR> where E is the cell emf.
 MR>       Po is the rated cell output power
 MR>       Rs is the diode's apparent resistance at rated current (Vf/If)
 MR>       Rload is the optimal load for maximum power transfer
 MR>       +/- is real or imaginary roots
The formula doesn't help a great deal, except as a "term" in a larger
differential equation. Too many dynamics.......
E moves about all thru the day;  Po needs a definition [what constraints?]
Rs shifts wildly with ambient temp;  Rload is variable as circuits are
switched and battery trends from flat to gassing, and is likewise moved by
ambient temp.
You might think to average some criteria. But, "averages" are also
misleading; "r.m.s." has a nice relevance; the entire math evaluation will
differ summer vs winter and time of day.
                                                              
 MR> Just punch the formula into the old 4 banger and let it rip.
Nah! Just file it!!   Cheers.....ALEC
... >>>>>> I have a filing system but I have misplaced it <<<<<<
--- PPoint 1.92
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