Dynamic State Estimation for Microgrid Structures

Abstract

In this article, the dynamic state estimation of the islanded microgrids problem is addressed. The electrical network and energy sources are represented as a set of Nonlinear Differential Algebraic Equations, with the aim to capture the nonlinear phenomena and a novel solution, by using a variation of the Kalman Filter ad hoc for differential algebraic systems, is presented. In this representation, the state is given by the voltage phasors at each bus and the variables related to the energy sources. The proposed algorithm permits not only to effectively obtain an estimate of the state variables but also it allows to recover these variables during the microgrid transient behavior. Moreover, the estimation may be carried out using fewer measurements than those needed by conventional static estimators. The performance of the proposed dynamic state estimator is evaluated via numerical experiments using two practical microgrids containing wind power and hydroelectric generators. This novel method has been tested for load variations and wind speed changes demonstrating its capabilities and efficiency.