Implementation of an Embedded Control for the Maximum Power Point Tracker in Photovoltaic systems

Abstract

The actual environmental problems and the increasing demand of energy around the globe have motivated the adoption of novel energy resources. In this transition the microgrids appear as a key element. The photovoltaic systems (PVSs) represent one of the main energy resources for microgrids (ˇGs), consequently the improvement of their efficiency has gained a special interest in recent studies. It follows that the maximum power point tracker (MPPT) controllers appear as one of the principal topics from these studies. In this work is presented the design and implementation of a fuzzy-logic-controller-based MPPT system applied to a PVS. The implemented controller operates based on the classic algorithm of Perturb and Observe (P&O); it controls the duty cycle of a DC-DC boost converter depending on both the changes of the supplied power by the panel and the duty cycle variations observed. The controller was implemented in a NI myRIO-1900 board and was tested under an experimental DC ˇG with a load capacity of 1 kW and a 190 V bus. The design of the fuzzy logic controller (FLC) considered a set of gains that allow its implementation on panels of different power outputs. The achieved results evidence that the controller operates satisfactorily under panels with a different power output. For instance, the controller not only reaches the maximum power point in a shorter time than a classic P&O controller but presents a similar behavior in steady state with low oscillations