"Ideal diodes" for solar array

[GTom]

Those who are after Schottky's might find these circuits on fleabay interesting: they act like diodes but their forward voltage is in the millivolt range:

Ailavi DC 4~28V 15A Anti Reverse Irrigation Ideal Diode Module

Or a bit different design & wider voltage threshold:
LTC4359 15A Solar Charging Anti Reverse Irrigation Ideal Diode

I am thinking on a series-parallel panel setup and thinking about something similar to protect the parallel groups against countercurrent (in case e.g. the port or starboard side is shaded).

[john61ct]

Maybe overthinking?

But if the science project yields benefits IRL, do please post results here!

[senormechanico]

They say 8 milliOHM, not millivolt drop.
There's a difference with solid state stuff.

[GTom]

Originally Posted by john61ct

Maybe overthinking?

Likely. The case when the blocking element becomes useful is when one of the parallel groups is shaded/out of the game and the active group starts to feed it besides of the controller (battery->panel loss at night shouldn't be problem with the controller in place).

Anyway, might worth that 10$, if I manage to get the thing in an MC4 compatible waterproof package I'll report back. MC4 packaged standard diodes (not Schottky "of course") are available but they add ~3% loss to the system if not more.

Originally Posted by senormechanico

They say 8 milliOHM, not millivolt drop.
There's a difference with solid state stuff.

From the first listing:

The voltage drop measured data (for reference only):
Load current of 2A voltage drop 0.0086V
Load current of 5A voltage drop 0.022V
Load current of 8A voltage drop 0.036V
Load current of 10A voltage drop 0.042V
Load current of 12A voltage drop 0.052V
Load current of 15A voltage drop 0.075V