"Larry Jaques" wrote in message
...
On Sun, 05 Nov 2017 07:37:28 -0800, Larry Jaques
wrote:

On Sun, 5 Nov 2017 08:09:56 -0500, "Jim Wilkins"
wrote:

from a small system. My DPS5015 switching regulator can be used to
find and charge at the maximum power point but it won't track
changes
automatically.

Interesting, but sort of a moot point without automation. Or is it?
Finding the MPP of the system might be good for a boost, even
without
the tracking, but I haven't seen any studies on that. I'll look for
some more articles on MPP to see.

Nope. Conditions vary so much that a single snapshot of an MPP in
time wouldn't be of much use. It appears that the MPPT controller
changes the resistance of the circuit so it continues to output max
power at all times, from 1 to 1000 times per second. (one of 84
million 400 thousand snapshots a day.

https://www.teachengineering.org/les...pveff_lesson03
(I know, k12 site, but it had the info I sought.)


http://lib.tkk.fi/Dipl/2010/urn100399.pdf

Finding the MPP with the DPS5015 shows me how much more current an
MPPT controller would give, compared to a direct connection from the
panel to the battery as with a PWM controller. I've read that an MPPT
controller isn't cost-effective for arrays of 200W or less, or for
trickle charging batteries whose voltage is already close to the MPP.
-jsw