Reduced-order Modeling of Active Rectifiers Under Different Droop Control Strategies

In dc microgrids, power sharing performance may not be identical among different droop strategies when cable impedance is not negligible. Furthermore, they have an effect on the system stability especially in presence of constant power loads. The corresponding reduced-order models are developed and their validity is confirmed by comparing against the full-order model. Converter dynamics is taken into account and its effect on small signal stability is discussed. Nyquist criterion is applied to evaluate the stability for proposed droop methods. Furthermore, the influence of power sharing ratio to system stability is also discussed. The results obtained by analysis are validated by detailed simulation studies in MATLAB/Simulink.