High-Frequency Resonance Analysis Between DFIG Based Wind Farm with Direct Power Control and VSC-HVDC

The direct power controlled doubly fed induction generators (DFIG) can remove phase-locked loop (PLL) which benefits the stability near fundamental frequency of VSC-HVDC and DFIG-based wind farm interconnection system. However, it will introduce broadband frequency coupling on the DFIG system. The influence of control delay and frequency coupling intensity on the VSC-HVDC and DFIG-based wind farm high frequency impedance characteristics will be studied in this paper. Furthermore, based on the equivalent single-input single-output small-signal impedance model, the occurrence mechanism of high-frequency resonance is revealed. Then the system stability and influencing effect will be analyzed.