Dynamic Prioritization of Critical Loads for Sustaining Power Distribution Systems upon Islanding

Abstract

Large-scale integration of distributed energy resources (DERs) in the power distribution system has challenged the conventional notion of a radial system with unidirectional power flow. The bi-directional flow of power from the consumer end raises concern for the protection systems in place to detect islanding phenomenon. However, the current standards/practices do not allow the DERs in an electric distribution system to stay connected in islanded mode except in a micro-grid mode of operation, which has designated controllers to maintain the stability of an islanded system. The work presented in this paper proposes the implementation of a technique to assign distinct priority levels to various critical loads in real-time based on voltage sensitivity factor. The proposed module decides the shedding order of these loads in real time depending upon system operating conditions in order to sustain an island from the point of disconnection stabilizing the power balance within the island.