Load shedding and Its strategies against frequency instability in power systems

Maintaining frequency stability is one of the important aspects in power system operations. As an emergency control action, load shedding (LS) can effectively protect the power system against frequency instability. In practice, its strategies include event-driven load shedding (ELS) and under-frequency load shedding (UFLS). This paper conducts comprehensive review and comparison for the two LS strategies. Discussions are also given on their coordination for more cost-effective frequency instability prevention. Simulation examples are provided to lead the study. Based on this work, a clear picture of the two LS strategies can be shown and deeper insight can be gained for better design and application of the LS strategies in practice.