Impact of DFIG wind power on power system small signal stability

Nowadays renewable energy provides about 1/5 of the electricity generation worldwide. Among all the renewable generation forms, wind power generation is regarded as one of the most developed and efficient ways to utilize renewable energy. With more and more wind power integrated into high voltage transmission grid, whether wind power will influence the small signal stability of power systems, what kind of impact it will bring about and how wind power will influence the system small signal stability attract more and more attention. In this paper, an analytical method will be proposed to analyze the impact of DFIG integration to power system oscillation modes and mode shapes. The foundation of this method is sensitivity analysis. Simulations are conducted on a 4-machine-11-bus test system. Simulation results show that the DFIGs introduce no poorly damped electromechanical modes. The states of DFIG hardly contribute to the electromechanical modes. Furthermore, the parameters of DFIG almost have no influence on the modes.