Roll Up Solar Panels / Ogre MPPT Controller
I would LOVE to get 10-12 amperes of 12 volt grade charging for my new group 31 Lifeline. But I have a motor-scooter size toad, that forces me to the roll-up kind of solar panel, and woe is me, the...
Forum Discussion
pnichols wrote:pianotuna wrote:
Hi Phil,
I'd love to know more about the solar magic system and the technology they use.
Don,
This document from TI may provides a pretty good explanation of how the SolarMagic module improves the harvest from solar panels:
http://www.ti.com/lit/an/snosb67b/snosb67b.pdf
OK, pretty interesting.
So if I get it, the SM is a per-panel MPPT gizmo. It bucks or boosts voltage as needed to match up the panel's amps to the amps of the other panels in the series string. Or to a reference panel, which should be selected as the one with the best sun exposure.
In doing so, the watts into the SM are equal to the watts out. Voltage might go down but amps go up, or vice versa. Since voltage is additive in series, we don't care that a panel's volts might be lowered in this process. Within reason I suppose?
The main benefit is to reduce the drag on the string of panels which are shaded or faced the wrong way at a given time.
Is that a good executive summary?
