Analysis of grid connected hybrid renewable energy system

Abstract

This paper proposes a DC-linked hybrid renewable energy system (HRES) connected to the grid through a three level neutral point clamped converter. The proposed structure consists of a wind generator (with Maximum Power Point Tracking (MPPT)), power limitation, and pitch control modes) with a flywheel energy storage system, a photovoltaic generator (MPPT and power limitation modes) with a battery, and a super-capacitor connected to each capacitor of the DC link of the three level converter. With the aim of managing the power flow between the HRES, the grid, and the variable load demand, we designed a power management strategy according to the global state of charge of the storage system, the weather conditions, and the load demand. In order to show the efficiency of the proposed structure and management algorithm, numerical simulation was performed using MATLAB/Simulink.