I've opened up a PWM5 solar charge controller and put an Arduino Pro Mini where the PIC 12F683 used to be. A potentiometer is used to control the PWM pulse width and I'm trying to steer the battery voltage to the desired 13.5 volt float point.
By Julian
Youtuber, shed dweller, solar charge controller aficionado
Could the charge pump and the high side driver be replaced by a single bootstrap high side driver like the tlp250?
Couldnt the microprocessor regulate charging voltage depending on ampers value? Why you play with the potentiometer since you dont know the current value?
"ive closed the loop by using my own brain" lol.. lovin it.. great vid man
Can you add thermal sensing to this. I would hate to have this go thermal runaway.
Why in particular have you chosen 13.5v as your target float voltage? (Why not say 13.8v or 13.2v for instance?)
Putting in for the first order! ololol Your brilliant.
I'm so gonna build that thing up once you've got some documentation for it 🙂
You thought about a ATTINY85? You don't need a crystal and its in a 8 pin DIP or SMD part.
This is awesome. The fact it is open source and the Arduino is the brains gives this a leg up on commercial charge controllers. I will defiantly follow this project cause the great thing with open source projects seems that they only get better. There will probable be a day where this will match/beat most charge controllers in its class and will be cheaper to boot. I will definitely think twice when go to purchase my next charge controller. Good job and Cheers!
Nice work Julian!
I see a download of an Arduino PID library in your future 🙂
cool stuff. lots of toys! you are pretty close in theory to what my little controller is doing. high farad capacitors in parallel with the solar input slows down the swings a little bit, making it easier to nail down that sweet spot….. but there are a ton of variables. i eventually want to set up two systems side by side, with identical panels and batteries, but different circuits to show the difference.