Impact of Shunt reactor to DFIG Connected to Series-Compensated Power System on Sub-synchronous Oscillation Characteristics

Abstract

The shunt reactor will affect the sub synchronous oscillation characteristics of the wind power system, and there is no paper that analyse this aspect. To this end, in the DFIG via series compensation transmission power system, use impedance scanning method to measure the total equivalent impedance of system side and DFIG side, the mechanism of the influence of the installation position and capacity of the shunt reactor on the sub synchronous oscillation characteristic of the system is analysed. The analysis results show that the larger capacity of shunt reactor, equivalent impedance effect is larger, the installation position that is very near the fan can reduce the resonant frequency and increase the resistance of resonance point, being far from the fan will increase the resonant frequency and the absolute value of the negative resistance in the resonance points, besides, the effect of parallel capacitor on system impedance is very small. Finally, the correctness of the theoretical analysis is verified by the time-domain simulation.