Sensitivity-based approach for real-time evaluation of transient stability of wind turbines interconnected to power grids

The growth of utilisation of wind turbines in the contemporary power systems, the transient stability (TS) evaluation has turned to a challenging issue in the modern power grids. An innovative and high-precision real-time method based on the transient energy function (TEF) is proposed which aims to evaluate the TS of power system in the presence of wind turbines. The proposed method is designed so that the initial point of TEF is calculated precisely by performing offline calculations. Structure preserving is used to guarantee the accuracy of the proposed method in order to consider the details of power system modelling. Moreover, the proposed method takes into account the impacts of the wind turbines controllers utilising new formulation based on a sensitivity-based approach. The new formulation is utilised to calculate the effects of the controllers reflected in the potential terms of TEF during the fault occurrence. As a result, in addition of considering fault-on trajectory, the latter technique causes reducing the computational burden and also guarantees accurate real-time assessment of TS. The simulation results demonstrate the efficiency and also comprehensiveness of the proposed method in calculation of critical clearing time and TS assessment.