Optimal Configuration Strategy of Under-Frequency Load Shedding for Power Grid Based on Correlation Degree under High Penetration Level of Clean Energy

Abstract

The under-frequency load shedding (UFLS) in the third line of defense of power system is one of the significant measures to prevent the rapid and continuous decline of the system frequency and ultimately maintain the stability of system frequency after disturbance. Meanwhile, when a large amount of clean energy is connected to the power grid, the frequency characteristics of the power system become worse. How to explore and exploit the optimal configuration strategy of UFLS under high penetration level of clean energy is a key issue to be solved urgently. Therefore, under the background of large-scale grid-connected clean energy, this paper deduces the correlation degree index which can effectively realize load shedding. On this basis, the improved scenario-based method is utilized to describe the uncertainty of clean energy. Further, the setting process of UFLS solution based on the adjustment power and steady-state frequency is proposed. Finally, taking the IEEE standard test system as an example, the validity of the proposed optimal configuration strategy of UFLS is verified by simulations and comparative analysis.