Modeling and stability analysis of hybrid AC/DC microgrid based on a hybrid model

Abstract

Hybrid AC/DC microgrid (MG) has attracted more and more attention due to its advantages such as better power sharing, improved system dynamics, and optimal management. But the complicated structure brings a great challenge to the modeling and stability analysis. In recent years, dynamic phasor model has been well applied in the modeling of AC MGs. Dynamic phasor tranforms sinusoidal quantities to constant quantities on the base of Fourier Transform and it makes the modeling procedure of AC MGs much easier. In this paper, a novel hybrid model of a droop-controlled hybrid AC/DC MG is developed with dynamic phasor model applied in the AC side and the conventional state-space averaging model applied in the DC side. Small signal stability Analysis is conducted with the help of the developed hybrid model to investigate the effect of the droop gains on the hybrid AC/DC MG. Conclusions of stability analysis are verified through time domain simulation in Matlab/Simulink.