II. PV system description: Maximum power extraction in PV system using fuzzy logic and dual MPPT control

摘要

In this paper proposes a new digital control scheme for a photovoltaic (PV) system using fuzzy-logic and a dual (MPPT) controller. To obtain the maximum electricity from the solar cells, the PV modules have two MPPT controllers. The dc voltage and current are controlled to track the maximum power point, where the PV modules feed the maximum output power. A MPPT technique is used to operate in the optimum power condition. The first MPPT controller is an astronomical two-axis sun tracker, which is designed to track the sun over both the azimuth and elevation angles and obtain maximum solar radiation at all times. The second MPPT controller controls the power converter between the PV panel and the load and also it implements a new fuzzy-logic controller (FLC) based perturb and observe (P&O) scheme to keep the system power operating point at its maximum. The proposed control scheme achieves stable operation in the entire region of the PV panel and eliminates the resulting oscillations around the maximum power operating point.