Distributed Frequency Control for DFIG WTs-based Islanded Systems

Abstract

This paper proposes a distributed frequency control available for the self-adaptive frequency regulation in DFIG wind turbines (WTs)-based islanded systems. The proposed control can empower all paralleled DFIG WTs to actively produce their transient power share of generation to vanish any frequency bias. Meanwhile, an undue response from any DFIG WT is averted. Effective coordination is realized by neighboring communication, so that centralized verbal broadcasts and competitive behaviors amongst DFIG WTs are all cast off. For sake of convenience, a 2-machine system is introduced to present the concept of the proposed control and deduce the analytical expressions of frequency dynamics. On this basis, the dependency of dynamic frequency performances on control parameters is then evaluated. It provides a guidance for parameter settings. Finally, the effectiveness of the proposed control is verified in a full-order 2-machine system and a wind power plant-based islanded system.