Intentional Island and Dynamic Analysis of a Micrognd

During the project of the distribution system's protection, it is necessary to consider the presence of distributed generators that demand modifications in the protection system design and create new operational possibilities, such as the planning and operation of microgrids. The microgrids' ability to operate as islands can contribute to improve the energy supply continuity indexes as well as reduce the costs of energy not supplied. In this paper, the under/over frequency and directional overcurrent relays are modeled through ATP-EMTP and applied to identify faults and create intentional islands. Furthermore, an analysis on the microgrid's islanded operation is conducted to verify the maintenance of voltage magnitude and frequency within the regulatory agencies' constraints. CIGRE's 14 bus test system is used to perform short circuit analysis considering the variation of resistance and fault type, to verify the effectiveness of coordination between these devices. The results show the effectiveness of coordination between the devices and the system's dynamics during the first few seconds after the intentional island.