Data-driven Coordinated AC/DC Control Strategy for Frequency Safety

Abstract

With high penetrations of renewable energy and power electronics converters, less predictable operating conditions and strong uncertainties in under-frequency events pose challenges for emergency frequency control (EFC). On the other hand, the fast adjustability of converter-based sources presents opportunities to reduce economic losses from traditional load shedding for EFC. By integrating DC power emergency support, a data-driven coordinated AC/DC control strategy for frequency safety - Coordinated Emergency Frequency Control (CEFC) - has been designed. CEFC coordinates both the initiation and control amount of emergency DC power support (EDCPS) and traditional load shedding. Based on real-time power system response data, CEFC ensures system frequency safety at a minimum control cost under non-envisioned operating conditions and large power deficits. A sufficient condition where data-driven modeling errors do not affect the precision of the control strategy for power system frequency is rigorously provided. Simulation results demonstrate CEFC's adaptability, prediction accuracy, and control effectiveness.