A Novel Contingency-Aware Primary Frequency Control for Power Grids with High CIG-Penetration

The ever-growing trend of Converter-Interfaced Generation (CIG) integration in electrical power grids has led to a tremendous concern about systems' inertia, stability, and frequency regulation effectiveness. During contingencies, like the loss of a large generator, the primary frequency control is deployed to compensate for the frequency drop. However, as CIG penetration grows, traditional primary frequency control becomes less effective in mitigating significant post-contingency frequency deviations. To address this problem, we introduce a novel control framework that fully utilizes the proportional primary frequency control concept manifested in the contingency-aware control discontinuity. The proposed framework collects information about the disturbance and redistributes control gains according to the pre-calculated optimal strategy employing dynamic properties of both synchronous generation and CIG. It incorporates a novel frequency security assessment using frequency majorant functions, providing a conservative low boundary estimate of the frequency nadir. Numerical studies demonstrate that this proposed control strategy reduces nadir deviation by 49% and shortens the transient period by 30%. Furthermore, we illustrate the optimization of droop control gains considering CIG characteristics, such as location and inertia, to enhance system stability by allowing CIGs to perform primary frequency control functions from synchronous generators.