A Novel PMU-Based Adaptive Coordination Strategy to Mitigate Modal Resonance between Full Converter-Based Wind Generation and Grids

To mitigate the resonance between the full converter-based wind generation (FCWG) and the grids, their modal interaction is usually coordinated off-line and requires the full system model. In this article, an on-line coordination strategy is proposed to achieve appropriate modal coordination in a model-free manner. First, the dynamic interaction mechanism is examined to quantify the modal interaction impact, which provides theoretical foundation of how FCWG controller parameter tuning contributes to modal coordination. With phasor measurement unit (PMU) equipped in the power grid, the essential oscillation information (e.g., the critical mode that relates to modal resonance) is acquired without detailed modeling of the power grid. According to the frequency range of critical mode, the proper controller in FCWG is selected for parameter tuning. On this basis, we employ an on-line coordination strategy by adjusting relevant controller parameters to accommodate corresponding changes of system operational conditions and thus mitigate the potential risk of modal resonance. Case studies are carried out to demonstrate how FCWG adjusts the controller parameters timely to improve the oscillatory stability under various operating conditions, and thus in turn substantiate the robustness and adaptability of the proposed strategy.