Research on the Modeling of SSO with RTDS for the DFIG with Series Compensated Transmission Line System

To study the impact of DFIG series compensation sub-synchronous oscillation(SSO) on the power grid, this paper establishes the DFIG with series compensation transmission line model based on real time digital simulation platform RTDS for the first time. The proposed model can reproduce typical 5.33-8Hz sub-synchronous oscillations, verifying the influence of series compensation degree, number of wind turbines, and wind speed. The simulation results show that as the series compensation degree decreases, the frequency of oscillation also decreases, indicating that higher series compensation degree is more prone to oscillation. As the wind speed increases, the frequency component that generates oscillations also decreases, indicating that the lower the wind speed, the easier it is to generate oscillations. Simulations were conducted on systems with different numbers of fans, and the simulation results showed that as the number of fans increased, the frequency component that generated oscillations also increased, indicating that the higher the number of fans, the easier it was to generate oscillations.