A network-considered short-circuit impedance phase angle modeling and current limiting method for energy storage

Abstract

This invention discloses a modeling and current limiting method for grid-type energy storage that considers the short-circuit impedance phase angle. Addressing the issue of existing transient analyses neglecting the short-circuit impedance phase angle, this method establishes a fault transient model under non-metallic short-circuit grounding scenarios, correcting the analysis error caused by traditional transient analyses that only consider voltage drops. Based on this, this invention constructs an adaptive virtual impedance based on voltage and current deviations and proposes a hybrid current limiting strategy for actual fault scenarios, combined with a ring current limiter. This improves the transient modeling theory of grid-type energy storage and provides a reference for enhancing overcurrent limiting capabilities under large disturbances. Hardware-in-the-loop simulation results show that this hybrid current limiting strategy can achieve effective current suppression throughout the entire fault process, laying a solid foundation for the safe operation of power electronic equipment.

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