Fast control strategy for stabilising fixed-speed induction-generator-based wind turbines in an islanded distributed system

摘要

Distributed generation systems (DGS) with fixed-speed induction-generator-based wind turbines (FSWT) are sensitive and vulnerable to voltage disturbances and reactive power deficiency. Consequently, the control and protection strategies for such a DGS should be prompt and precise to avoid undesired wind generator cutting off. This study investigates and analyses the dynamic characteristics of an FSWT to reveal the behaviours of an FSWT under disturbances. Then a fast control strategy for stabilising an islanded DGS is proposed. The main contributions of the control strategy are: the total amount of reactive power compensation and load shedding may be determined precisely; all the operation execution points may be decided accurately to improve DGS stability. Furthermore, the implementation of the fast control strategy is also discussed. A case study is presented to demonstrate the effectiveness of the proposed method.