Load Shedding Application within a Microgrid to Assure Its Dynamic Performance during Its Transition to the Islanded Mode of Operation

Dorel Soares Ramos, Tesoro Elena Del Carpio-Huayllas, Ricardo Leon Vasquez-Arnez

Department of Electric Power and Automation Engineering, University of S?o Paulo, S?o Paulo, Brazil.
FDTE (Foundation for the Technological Development of the Engineering Sciences), S?o Paulo, Brazil.

DOI: 10.4236/epe.2013.57047                

Abstract

This article presents the simulation results and analysis related to the response of the generators within a microgrid towards an accidental overload condition that will require some load shedding action. A microgrid overload can occur due to various reasons ranging from poor load schedule, inadequate switching of circuits within the microgrid, outage of one or more generators inside the microgrid, illegal load connections by some low voltage consumers, etc. It was observed that among the main factors that determine the survival of the microgrid during its transition from the grid connected mode to the islanded mode of operation are the size and type of the load connected (passive or dynamic load) as well as the length of time during which the unexpected load is connected. Models of a speed and voltage regulators of a diesel generator, and important for coping with the overload conditions are provided in the paper. The novelty of the work lies in the load shedding simulation and analysis of the specific generators studied herein, regarding that in many countries the microgrid technology is seen as an important alternative towards the ever increasing load demand and also to assist the system during periods of blackout.

Keywords

Distributed Generation; Islanded Operation Mode; Load Shedding; Microgrid Systems

Conflicts of Interest

The authors declare no conflicts of interest.

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