Hello,
A group of students along with myself are working on a DC-DC Converter with an MPPT as our Senior Design Project. After a few weeks of thinking through differing designs we decided to go with one which implements the MPPT first and then sends the output voltage and current to a DC-DC converter to adjust the voltage for a battery to be charged at a constant voltage. The MPPT is going to be controlled by an arduino microcontroller following the Perturb and Observe algorithm. The output voltage will be adjusted using a MOSFET. The resultant voltage and current will then go to the DC-DC Converter and be adjusted for a constant voltage out. Many of the papers I have read do not follow the same design process and I am therefore trying to understand why. Any help would be greatly appreciated. Thanks.

 

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Many of the papers I have read do not follow the same design process and I am therefore trying to understand why. Any help would be greatly appreciated. Thanks.

That's because your design is totally flawed.

MPPT has one purpose; to put maximum charge current into the battery at all times.

A voltage regulator has one purpose; to reduce current as needed to keep battery voltage constant.

The two concepts are mutually exclusive, and if the voltage regulator is last it will negate any advantages of the MPPT while it is regulating voltage.