Reflection Coefficient Stability Criterion for Multi-Bus Multi-VSC Power Systems

This paper proposes a reflection coefficient stability criterion for multi-bus power systems with multiple voltage-source converters (VSCs). In the method, VSCs are modeled as two-port networks, which are then characterized by the incident and reflected power waves, as well as their ratios, i.e. reflection coefficients. Two superior features over the impedance-based stability analysis are provided, which are no need for system partitioning to avoid unstable subsystems, and the identification of relative stability and the critically oscillating frequency at each bus of the power system. Case studies with experimental results demonstrate the effectiveness of the approach.