Comprehensive Stability Analyses for Hybrid AC/DC Microgrids with Multi-Paralleled Interlinking Converters under Distributed Control

Hybrid AC/DC microgrid (MG) is a promising electrical power system architecture that enables to harmonize AC and DC energy conversions. Due to the complicated configuration, comprehensive stability analyses for a complete hybrid MG still stand as an unsurmountable challenge. To address this issue, this paper decomposes the MG system into several electrical modules, i.e., an AC source, a DC source, multi-paralleled interlinking converters (ICs) and line impedances. These modules are first individually modeled in the small signal sense. They are then combined to establish a full autonomous mathematical expression for characterizing dynamics of the hybrid MG. To investigate MG system stability, the influences of diversified operating points, line impedances and the selected key control parameters are examined by evaluating eigenvalue loci of the derived mathematical model. Time-domain simulations reveal the perfect matching between the results given by Matlab/Simulink and eigenvalue loci plots.