Mppt
Contents
EC MPPT algorithm
Overview
This describes the MPPT algorithm present in the XO-1.5 embedded controller. When operating from a PV solar panel the available power can be very dynamic even in seeming very sunny conditions. In many cases the maximum power available from the solar panel is less than the maximum power draw of the XO-1.5. The maximum power input to the XO-1.5 is 25W but the most common OLPC solar panel in use is only rated at 10W. This can create up to a 15W power deficit.
The voltage output of a PV panel is related to its ouptut current. The VI curve for the OLPC panel looks like this
As the current draw increases from the panel the voltage decreases. This creates a power curve that looks like this
So the the maximum power point of a PV panel is obtained when you maximize both the voltage and the current.
Definitions
Scream Detect
Assumptions
More on this after I sleep
Flow Chart
Wikimedia seems to hate trying to render my .svg . Here's a link to the .svg file Media: mppt.svg
The dia file is also available.
And here's the same thing as pdf:
