Settling-Angle-Based Stability Analysis for Multiple Current-Controlled Converters

This letter proposes a settling-angle-based stability criterion, as the extension of determinant-based general Nyquist criterion, to facilitate the stability analysis of nonminimum phase power systems with multiple current-controlled converters. Using only the phase information of converter impedance in the
$dq$
-frame, the proposed stability criterion can accurately demonstrate the system stability and identify resonance sources according to the settling angles of the overall system and its subsystems, which are validated by simulation and control hardware-in-the-loop results.