Impedance Modeling and Stability Analysis of DFIG-Based Wind Energy Conversion System Considering Frequency Coupling

Impedance-based stability analysis is an effective method for addressing a new type of SSO accidents that have occurred in recent years, especially those caused by the control interaction between DFIG and power grid. However, existing impedance modeling DFIGs mostly focused on single converter, such as GSC or RSC, influence RSC GSC, well frequency coupling effect inside converter are usually overlooked, reducing accuracy analysis. Hence, entire proposed this paper DFIG-based WECS, taking factors into account (e.g., DC bus voltage dynamics, asymmetric current regulation dq frame, PLL). Numerical calculations HIL simulations RT-Lab were used to validate model. The results indicate model with more accurate, it capable accurately predicting system’s possible resonance points.