Comparative Study between Common and Individual MPPT Controller Using Fuzzy Logic Control for Hybrid System (Photovoltaic/Wind Energy Conversion System)

Abstract

This paper aims to hybridize photovoltaic systems (PVs) with wind energy conversion systems (WECs) by using different architectures, with a comparative study to distinguish the best hybridization method that gives the best performance. The first architecture uses an individual maximum power point tracking (MPPT) controller for each system independently. The photovoltaic generator is connected to the DC/DC converter and is controlled by fuzzy logic control (FLC) to track maximum power. In the WECs system, which is based on a permanent magnet synchronous generator (PMSG), the DC/DC converter is also controlled by FLC to maximize its output power. The second architecture uses a single MPPT controller for both systems; the PV generator and AC/DC converter of the WECs are connected to a common DC/DC converter controlled by the FLC. The hybrid system is connected to the grid via an inverter, which is controlled by voltage-oriented control (VOC) to separate the control of the active and reactive powers. The system studied was specially designed to be installed in the building, consisting of a photovoltaic system providing 25 kW and a WECs composed of three small turbines, each providing 8.5 kW. The MATLAB simulation results are presented under varying conditions of sunlight, wind speed, and load requirement, proving that; the using of an individual MPPT controller gives better performances than the single MPPT controller. However, the last topology provides more power than the first topology (over 1 kW) because of the reduced number of converters used.