Three-Phase Steady-State Models of Distributed Generators with Different Control Strategies

Abstract

This paper proposes three-phase steady-state models for distributed generators (DGs) with different control strategies and an augmented rectangular load flow method is used for three-phase distribution systems. For two kinds of DGs with power electronic devices: photovoltaic power generators and doubly-fed induction generators, the nodal voltage equations and the output power equations are derived. Moreover, under the unbalanced conditions, the control strategies are applied and formulated as the function of the nodal voltage and the injected current to reduce the effects caused by the negative-sequence components. Furthermore, the models are incorporated into an augmented rectangular load flow method with nodal voltage and injected current as state variables in three-phase systems. Case studies are conducted to verify the correctness and accuracy of the proposed models by comparing the results obtained from MATLAB and PASCAD.