A dynamic modeling framework for future distribution energy systems

This paper recognizes that the large resistance to reactance line ratio in distribution systems may create strong coupling between real and reactive power dynamics. To model this coupling, a new coupled real-power voltage dynamic model for future distribution energy systems with a large penetration of distributed generation (DG) units is derived. The proposed dynamic model offers an intuitive physical insight into the interaction between the electromechanical and electromagnetic phenomena. This model, furthermore, provides a better understanding of the decentralized nature of distribution energy systems where each DG represents a sub-system of the whole system. The theoretical findings are applied to investigate the small-signal stability of a real-world distribution system on the island of Flores. The results indicate that if the primary control of DGs are designed based on the decoupled model, frequency and voltage stability problems may occur in distribution systems.