Modelling and control of distributed energy resources in electric distribution grids

Abstract

To address the increasing environmental pollution problem due to the use of fossil fuels, as well as its shortage, Distributed Energy Resource (DER) systems based on renewable energy sources are attracting much attention. However, deployment of DER poses a challenge to grid security. Renewable energy sources are highly intermittent or at times random, and possibly having bi-directional energy flow. These characteristics can lead to excessive voltage fluctuations in the grid which fall outside of the range stipulated in Singapore’s regulations. Thus, a sensible control system becomes particularly important. Since DERs might be affiliated with different users, decentralized control can be used. Decentralized control allows each DER to be managed separately, thus greatly increasing the fault tolerance and stability of the grid. In this project a model of a distribution network comprising various types of DERs, including PhotoVoltaic Systems (PVS), Battery Energy Storage Systems (BESS), and Electric Vehicle Charging Stations (EVCS) is developed. A building model is also constructed as a conventional load. Decentralized control modules are built for each DER. These control modules ensure the proper distribution of power to maintain the voltage of a microgrid within the prescribed range while meeting the demands of the load. Keywords: Distributed Energy Resources (DER), Decentralized control.