Simple MPPT solar panel charge controllers

[Buckiller]

Against the rules to resuscitate old topics?

I found this topic from Google when I was building my website. I'm an undergraduate ECE major and MPPT was our senior project. I haven't totally finished the website, but the MPPT project page is mostly finished: http://bama.ua.edu/~bwbuckley/mppt.html

Very cool to read the progress you're making BillyDoc, wondering if you ever finished?

[scruffy.mogwai]

This is for gonzo and any others that are struggling with the claim that MPPT can increase your energy yield by up to 30%. This is NOT getting something for nothing. A sacrifice is made within these devices.

Disclaimer: Some facts and definitions are modified to help me explain the concept at a reasonably simple level.

Just say you usually get 12V from your panel(s) at full sun. In less sun that value drops. what a MPPT controller can do is keep the voltage at 12V (it has limitations though) at the sacrifice of current.
This is because that voltage and current are inversely proportional, that is, for the MMPT controller to keep the voltage at 12V when the panels are at <12V, the current is decreased to provide that extra increase in voltage.

[scruffy.mogwai]

Just stumbled across this. Read the following sections of the site:
What is a Charge Controller and Why Do I Need One?
Controlling Voltage: PWM vs. MPPT
http://blimpyb.com/diy-solar/mppt-ch...ntroller/3880/

[Redtick]

This controller has been getting good reviews and the price is lower than most.

http://www.roguepowertech.com/

[anilpaulbaby]

Hi, am new in forum.i am waiting you finish this project

[powerabout]

Originally Posted by scruffy.mogwai

This is for gonzo and any others that are struggling with the claim that MPPT can increase your energy yield by up to 30%. This is NOT getting something for nothing. A sacrifice is made within these devices.

Disclaimer: Some facts and definitions are modified to help me explain the concept at a reasonably simple level.

Just say you usually get 12V from your panel(s) at full sun. In less sun that value drops. what a MPPT controller can do is keep the voltage at 12V (it has limitations though) at the sacrifice of current.
This is because that voltage and current are inversely proportional, that is, for the MMPT controller to keep the voltage at 12V when the panels are at <12V, the current is decreased to provide that extra increase in voltage.

except the only way to raise the voltage of a lead acid is to push more current in till you have enough to raise it to that voltage

[BertKu]

I just inquired about and ordered the very simple but effective LTM8062. It only needs 4 external components and it allows you to charge up to 20 ampere by paralleling 10 devices (LTM8062s). Would anybody need 100 Ampere, just keep on paralleling. Input is a 36 cell solar panel charging either 4 cell li-Ion , Li-Poly , 5 cell LiFePO4 or 6 cell lead acid batteries. Will let you know when I received the product and have tested it.
Bert

P.S. The pin layout is a nightmare, 77 of them centre to centre 1.33 mm ( 0.0523 " !!!) One could make a small through hole printed circuit board and solder wires from the other side. The question is , how stable will it be. I have never seen sockets for 77 pin BLGA package. Alternative one could use maybe watch strap pins which has a little spring section and solder those ones in a pcb.