Impacts of AC/DC Coupling on Control Interaction Assessment in Power Systems with Black-Box Models

This work investigates how AC/DC coupling dynamics influence control interactions and stability in power electronic–dominated power systems. Prior studies often assess controlinteraction risks by considering either the AC or the DC subsystem in decoupled conditions, assuming that each side neither induces nor affects the stability behavior at the other side. Such simplifications, however, can lead to incorrect stability conclusions, particularly when the available system knowledge is insufficient to construct a fully informed stability assessment.