MPPT solar battery charger

[iw2fvo]

Steve,
the program controls both the load disconnection and the external power .
You can set the voltages at your choice.
Here is the piece of code. The whole code is not optimized : I am not a software expert as I told at the beginning. There are a lot of comments on the program.
I think that a software guy could improve the code in a significant way. BTW it is still working at my home.
regards,
Ambrogio
iw2fvo

' LOW VOLTAGE PROTECTION ...and load control..................................

IF ( VB<11800 ) THEN ' BATT LOWER THAN 11.8 Vdc
U_VOLT=1 ' SET UNDER_VOLTAGE FLAG
LOW LD_EN ' DISABLE LOAD
LOAD=0
U_FLG=1
ELSE
IF ( VB>12600 ) THEN ' IF VBATT MORE THAN 12.6 Vdc
U_VOLT=0 ' RESET UNDER_VOLTAGE FLAG
IF U_FLG=1 THEN
HIGH LD_EN ' ENABLE LOAD
LOAD=1
U_FLG=0
ENDIF
ENDIF
ENDIF

IF (U_VOLT=1) AND (EXTPWR_OK=1) THEN
LOW EXT_PWR_RLY ' ACTIVATE EXT POWER RELAY
EX=1
ELSE
IF U_VOLT=0 THEN
HIGH EXT_PWR_RLY ' RELASE EXT POWER RELAY
EX=0
ENDIF
ENDIF

IF U_VOLT=0 THEN
IF PB_3=0 THEN
if LOAD=0 THEN
LOAD=1
ELSE
LOAD=0
ENDIF
IF LOAD=0 THEN
LOW LD_EN
ENDIF
IF LOAD=1 THEN
HIGH LD_EN
ENDIF
WHILE PB_3=0 : WEND
ENDIF
ENDIF

[EarlyBird2]

My rules for programming in order of importance.

1 It works
2 It is easy to follow
3 It is easy to modify

My definition of a good program is

It works

Which yours does except for one minor detail. So the question is whether to rewrite the program or not to solve this cloud issue? Personally I would rewrite the program because I would learn by doing so. I only wish I had the hardware.

[iw2fvo]

As far as the cloud issue I wikll modify the program to improve stability.
I will do the modification to the code tomorrow and I will then test it for some days expecially when cloudy.
If ok I will post the mod later on. The mod will involve the ON STATE code only.
Thanks
Ambrogio
IW2FVO
North Italy

[iw2fvo]

I am posting the picbasic program B_4523 mainly modified to avoid oscillation among the ON state in particulary cloud sky condition.
I did minor changes as reported in the .txt program headlines.
Thanks to all of you for the suggestions provided.
Regards,
Ambrogio
IW2FVO
North Italy

[iw2fvo]

Good day,

I connected my charger to the PV and I left it for about 10 days having good results in all the sun conditions available in that period of time.
The final code together with the photo of the prototype implementation is attached to the present mail .
Regards,
Ambrogio
IW2FVO
North Italy

[Demon]

Congratulations!

Robert

[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