Design of buck-boost converter for solar

Joined Jun 25, 2018
1
With single DC-DC converter is it possible to track maximum power from solar and maintain constant voltage at output of DC-DC converter? I have been designing buck-boost converter to track maximum power from solar and maintain constant voltage at output of converter assuming solar excess power will charge the battery and load deficit will be supplied by battery.

Last edited by a moderator:

MrAl

Joined Jun 17, 2014
8,372
With single DC-DC converter is it possible to track maximum power from solar and maintain constant voltage at output of DC-DC converter? I have been designing buck-boost converter to track maximum power from solar and maintain constant voltage at output of converter assuming solar excess power will charge the battery and load deficit will be supplied by battery.
Hi,

You can max power track if you have a true "power sink". That is, something that can take a power level up to the maximum that the array can put out. This includes the power line itself in line tied applications, and also batteries like lead acid batteries as long as they can take the full power of the array.
If there is another load, then the battery can take the remaining power as long as the charger is set up to allow the current needed in order to load the array to maximum power.

So in short, if you have loads that can always take the maximum power, then you can max power track. If the total load power drops below the max of the array, then there will be times when the array is not being fully utilized.

HIShourov

Joined May 24, 2021
1
With single DC-DC converter is it possible to track maximum power from solar and maintain constant voltage at output of DC-DC converter? I have been designing buck-boost converter to track maximum power from solar and maintain constant voltage at output of converter assuming solar excess power will charge the battery and load deficit will be supplied by battery.
I need this file pdf

MrAl

Joined Jun 17, 2014
8,372
I need this file pdf
Basically you adjust the battery charge current while monitoring the array voltage and current and try to maximize the array voltage and current product P=V*I. This 'max power point' will vary with insolation quite a bit so it is a dynamic feedback process.
Once the battery becomes full charged, if that ever happens, then the array can no longer be operated at the max power point but at least until then the batteries charge as fast as possible although you also have to limit the battery charge current to the max allowed charge current.