Algoritmo de limitação de potência para conversores fotovoltaicos

Abstract

The main purpose of the DC-DC converter controller in a photovoltaic inverter is to extract the maximum power from the solar panels. For this, the maximum power point tracking algorithms (MPPT) are used. However, with the photovoltaic systems’ high penetration in the electrical grid, it is necessary that besides of maximum power extraction of panels, the control limits the power generation in overloading cases and when inverter input limits are exceeded. In this context, the present study proposes a limited power point tracking algorithm (LPPT). This algorithm aims to maintain the system between suitable limits, make a transition of maximum power point to a power reference point that automatically corresponds to those limits, contributing to the inverter operation. To validate the studies developed during this research, computational and experimental results are presented and compared using a boost converter prototype and a prototype composed of three boost converters connected in parallel to a DC bus. The computational and experimental results show that the proposed technique, in both prototypes, achieves that the system automatically finds the points of maximum and limited power.