Design of an adaptive protection system for microgrids with distributed energy resources in accordance with IEC 61850-7-420

Distributed Energy Resources (DERs) bring many technical challenges, which can be better managed in small and more manageable networks such as microgrids. One key challenge is the protection of microgrids where bidirectional power flows, DER fault current contributions, and dynamic changes in the microgrid call for advanced protection philosophies. This paper proposes an Ethernet-based adaptive protection scheme for microgrids penetrated with DERs. The proposed ideas show how such a novel protection system can be designed and developed in accordance with the IEC 61850 standard and specifically its recent extension on DER systems. The paper demonstrates how the information data models of DERs given in the IEC 61850-7-420 standard could be used in developing such an adaptive protection system. IEC 61850-7-420-based information modelling of example DER systems is discussed. Specifics of the information exchange in the communication network and the developed central control are deliberated.