Study on the Transient Power Angle Characteristic of Doubly-Fed Induction Generator

Doubly-fed induction generator (DFIG) wind turbine has become a mainstream machine of wind generators in China. As the different operational characteristics between the DFIG and synchronous generator (SG), the large amount of DFIG-based wind generators installed in the grid may bring a series of impacts on the dynamic behaviors of power system. In order to study the DFIG transient characteristics on the condition of the voltage dips happening in the power system, a definition of the DFIG power angle is given and the effects of the converters on the DFIG power angle are discussed. On this basis, the transient angle characteristic of the DFIG is derived. The DFIG transient characteristics are performed by Matlab/Simulink software, the simulation results demonstrate that the DFIG has the resemble power angle characteristic of SG and prove the effectiveness of the derivation process, which lay a foundation for the study on the interactions between the DFIG and power system.