Grid integration of wind and photovoltaic hybrid energy system

Abstract

Hybrid energy system usually consists of two or more renewable/nonrenewable energy sources. Currently hybrid systems involving wind power as one of the constituent along with fuel cell and/or photovoltaic power are more appealing. The main purpose of such hybrid power systems is to overcome the intermittency and uncertainty of wind energy and to make the power supply more reliable. Hybrid wind power with fuel cell can avoid the drawback of wind power intermittency, since fuel cell can act as an energy barrier and adjust the power output effectively. Wind power and solar energy can be combined into a hybrid system, especially for the power supply for remote areas where the cost of transmission line is too high. Another advantage of this kind of hybrid system is that they are both renewable energies, which is compatible to the environment. In order to deliver the stable power to the load, a substantial battery bank is needed, which enhances the size of the system, cost and also causes environmental pollution. The deployment of battery can be avoided by directly connecting the hybrid system to the grid. The work presented in this paper consists of modeling and simulation of wind and photovoltaic hybrid energy system inter-connected to electrical grid through power electronic interface. The power conditioning system is implemented to control power electronic circuits and system performance is evaluated for different input power levels and load variation.