Paper Title
Enhancement of Island Microgrid Transient Stability by Battery Energy Storage System

Abstract
This paper investigates the transient stability of the island microgrid with both photovoltaic PV system and wind power system. An offshore island in Taiwan has been selected for demonstration of microgrid with high penetration of renewable energy. To reduce the diesel generation cost, a photovoltaic PV system and battery energy storage system have been installed. Another renewable energy of 160 kW wind farm will be installed to increase the renewable energy on the island. To restore the stable system frequency after contingency disturbance of generation tripping, an energy storage system (ESS) has been applied for fast power discharge. To ensure the system transient stability, the impact analysis of the microgrid with such a high penetration of renewable energy has been simulated in this paper. The response of system frequency and power output of diesel generators after the sudden tripping of renewable generation systems has been derived by considering the mathematical modeling of diesel generators (DG) and ESS. It is found that the island microgrid can restore its steady state operation after the severe disturbance caused by sudden tripping of diesel generators and renewable energy when the fast power discharge of energy storage system is executed.