Power Flow Control of PV-Wind-Battery Hybrid Renewable Energy Systems for Stand-Alone Application

Abstract

The main problem in renewable energy system is the variation in power generation from time to time due to the intermittent nature of the renewable sources. Miss matching between power generation and load power causes a deviation from the desired voltage and frequency in power supply. A power flow control of a standalone photovoltaic-wind-battery Hybrid Renewable Energy System (HRES) for stand-alone application is presented here to balance the power generation and load power. Photovoltaic (PV) and wind are the primary power sources and battery acts as backup source to balance the power generation and load power. In spite of sudden load changes and changes in the power generation from PV power and wind power the power balance between the supply and demand effectively maintained by the proposed fuzzy logic controller (FLC). All the renewable sources and backup source are linked to a DC bus through dc-dc converter and the DC bus is connected to AC load through a voltage source inverter. A control strategy is implemented with fuzzy logic controller for smoothing of the power fluctuation and at the same time to maintain the battery state of charge (SOC) with in allowable limits. The various components are modeled and simulated in MATLAB/Simulink. Simulation results justify the ability of proposed controller to balance the power generation and load power.