Fuzzy controller based for photovoltaic maximum power tracking

The voltage of the DC appliances is nominally 12 V as the array voltage is varying over the day, a step-up and down (which is known by the buck-boost) DC-DC converter is required. A simple buck- boost converter is used to deliver the required output voltage. The control input is a pulse-width-modulated signal with a duty cycle continuously variable almost from zero to unity. Several types of control algorithms can be used with this converter topology. The simplest of the control schemes applied to a buck-boost converter is voltage control mode, which senses the output voltage and compares it with a reference. The reference voltage is the online maximum power (MP) points that determined through the application of the fuzzy regression model (FRM). In this paper the analysis, modeling and simulation of a new photovoltaic (PV) MP tracking scheme using the fuzzy logic (FL) controller is presented. A comparison between the fuzzy logic and the PI controllers are introduces to follow the MP through the day.