Islanding detection in a distribution system: A pattern assessment based approach using Concordia analysis

Distributed generation (DG) has acquired lots of importance in power industry in recent times. Integration of DGs helps in improving power quality, meeting high demand and maintaining smooth power grid operation. However, incorporation of DGs create complexity in power system protection schemes, such as unintentional islanding. Unintentional islanding has serious consequences on the serviceability and protection of the grid. The proposed methodology is based on voltage measurement directly from a micro-phasor measurement unit ($\mu\text{PMU}$) and performing Concordia analysis on these signals. Through the technique, it is assessed whether a disturbance occurred at the point of common coupling (PCC) is due to fault or an islanding operation. Various MATLAB simulations are performed using the proposed algorithm to justify its efficiency. Such events are performed on a doubly-fed induction generator (DFIG) based micro-grid.