Implementation of Adaptive Protection Scheme for Microgrid using IEC 61850 Communication Protocol
The existing electrical power system is experiencing radical changes in parallel with the growing integration of Distributed Energy Resources (DER) such as Photovoltaic (PV), Wind Turbine Generators, Fuel Cell etc. DERs with locally connected loads create subsystems within the main grid which are termed as microgrids. As microgrid becomes an important part of the distribution system, issues and challenges arising from its implementation should be addressed. Amongst many such issues such as voltage regulation, phase balance, reactive power control, stability etc., protection is a major challenge for the microgrid. In view of the issues related to microgrid protection, this thesis discusses the inadequacy of the conventional protection scheme, fault behavior of inverter interfaced DERs, and impact on the coordination of relays. The thesis also proposes the adaptive protection algorithm to be applied with extensive IEC 61850 communication protocol between Microgrid Central Protection Unit and relays. A small laboratory based microgrid was setup to prove the proposed algorithm.