A Unified Dynamic Characterization Framework for Microgrid Systems

A systematic, automatable, unified methodology is presented for the modeling of non-linear large-signal dynamics and eigenvalue analysis of microgrid systems. Unlike nodal-based simulators and typical state-variable methods that require Kirchhoff’s current law analysis, a state-space model is systematically derived from the netlist of the equivalent qd microgrid circuit model. The model may be used to conduct time-domain simulations and analyze system response to large transients. Additionally, system eigenvalues may be analyzed with respect to inverter control gains and system parameters to assess small-signal stability and sensitivity. The dynamic model is verified against existing experimental results, and small-signal stability results are presented.