MPPT solar battery charger

[iw2fvo]

Hi to all of you in the forum.
My MPPT charger is working since last June with no problem.
In this period I have no possibility to go on with my electronics hobbies.
I would like to know if someone has reproduced this project and has introduce some improvements.
Just to know !
Thanks
Regards,
Ambrogio

[harryweb]

HI IW2FVO,
I plan to use your schematics and parts of your code for my project (just ordered 2x100w PV, now need battery)
I would like to know what do you mean (schematics) replace D1 with ideal diode ?
It could take some times to make my project because of the season.
Congratulation for your work
Regards - 73'
F1SLU
Herve

[iw2fvo]

Hi Herve,
D1 introduce a voltage drop that impact on the whole system efficiency. This loss can be calculated an depends on current and diode performance in terms od forward voltage drop.
I used an ideal diode circuit to replace D1 during my last test at the bench only. I have not introduce it on my final circuit because of the space on the board.
You could find out a lot of these circuits here :
https://www.google.it/search?q=ideal...L&ved=0CCAQsAQ
You can also google " ideal diode solar " for additional info.
I do suggest to calculate the power saved and evaluate if really worth. It is up to you !
I will really start without it.
Best regards,
iw2fvo, Ambrogio

[harryweb]

Hi Ambrogio,

I just finished to install my solar panels 2 weeks ago. (Yes... I'm a turtle...)
As I doesn't make any charger I bought a cheap MPPT solar charger from Ebay (china) and it's a fake MPPT (just PWM).
So I've made the PCB for my real MPPT solar charger. Using most same parts as your schematics (just using other equivalent parts and not ACS712 but a maxim current sensor)
I have to modify your source program. :-)
I just would like to ask you, if you're happy with your charger/program, or did you make any changes ?
I have 220W solar panels.
I will give some news about the MPPT charger asap, I just received 5 PCB from... china today.... Have to solder now.

regards and 73
F1SLU Hervé
Best regards

[iw2fvo]

HI Herve,
It is still working well and no additional modification was introduced to the program.
I introduced an IDEAL DIODE found on the Ebay in place of the diode: it is OK.
I think the state machine portion of the program could be improved sometime...
My system has no PCB: do you have a spare one for me ?
All the best,
73, Ambrogio

[harryweb]

Hi Ambrogio,

My schematic is a bit different, so my PCB too ! As I have 220W panels some choice have to be done, and I also want to use serial to log on my computer. I think to make a python script to do that. I will upload picture of the schematics and PCB here but next week because I have it at work.
OK for the ideal diode. May be I will buy some of them ...
73, Hervé

[iw2fvo]

Thanks,
I will like to see it .
73, Ambrogio