A Linear Quadratic Gaussian Controller for a Stand-alone Distributed Resource Unit-Simulation Case Studies

Abstract

This paper develops a dynamic model and designs a control system for autonomous operation of a stand-alone distributed resource (DR). A stand-alone DR includes a distributed resource and a local load which are interfaced electronically. The DR is represented by a DC voltage source in series with a three-phase voltage-sourced inverter and an R filter, and the local load is modeled by a parallel (S) network. A state-space dynamic model is developed for the DR including the (S) network. Based on dynamic model of the DR, a controller is designed to maintain stability and control voltage and frequency of the stand-alone DR. Performance of the stand-alone DR for various scenarios of operation is evaluated based on digital time-domain simulation studies in the PSCAD/EMTDC software environment. The simulation results verify effectiveness of the designed control system in terms of maintaining voltage, frequency and stability of the stand-alone DR.