Small Signal Stability Analysis Of DFIG Based Wind Energy Conversion System

ABSTRACT This paper presents the state space modelling of Doubly Fed Induction Generator (DFIG) for small signal stability based Wind Energy Conversion System (WECS). A detailed mathematical model of wind turbine, DFIG machine and power converters is presented in this paper to derive the complete non linear dynamic equations of the studied system. The gains of PI controller in Rotor Side Converter (RSC) and Grid Side Converter (GSC) are obtained by butterworth polynomial method to improve the dynamic performance of DFIG and the power system stability. DFIG model connected to the infinite bus is studied under different operating conditions such as changing generator parameters under constant wind speed. Small signal stability of this linearized system is carried out by eigen value analysis. Finally, this paper presents an analysis of the dynamic behavior of DFIG under different conditions. The system under study is executed by using MATLAB/Simulink package. The whole system of DFIG is verified for constant wind speed. The system is tested using different values of generator parameters to determine the preferred ranges for the system stability. The results are performed to prove the importance of the proposed controllers. Keywords: DFIG, Eigen Value, Taylor Series, Wind Turbine Control, Stability.