Wide Frequency Band Active Damping Strategy for DFIG System High Frequency Resonance

As a popular renewable power generation solution, the Doubly Fed Induction Generator (DFIG)-based wind power system may suffer from High Frequency Resonance (HFR) caused by the impedance interaction between the DFIG system and the parallel compensated weak network. A wide frequency band active damping strategy for DFIG system HFR, including a high-pass filter and a virtual resistance, is proposed in this paper. The advantages of this active damping strategy are: 1) no resonance frequency detection unit is required; thus the control complexity can be decreased; and 2) no active damping parameters adjustment is needed within certain wide frequency band; thus the robustness of the proposed active damping strategy can be improved. The parameter design of the high-pass filter cutoff frequency and the virtual resistance are theoretically analyzed with the purpose of satisfactory active damping. A 7.5-kW down-scaled experimental setup is built up for the experimental validation of the proposed active damping method.