Abstract:
The DC microgrid contains many converters and complex structures. To simplify the stability analysis of the DC microgrid, this paper first divides the system into the converters and the line network. It builds the open loop transfer function matrix of the DC microgrid by combining the port impedance of the converter and the node admittance matrix of the line network. Then, based on this open loop transfer function matrix. The eigenvalue method is used to analyze the sensitivity of the system stability to different converters. Finally, according to the converter whose sensitivity contributes the most to instability, additional active damping is carried out to enhance the system damping and improve the system stability. Matlab/Simulink simulation examples verify the effectiveness of the stability analysis method and control strategy.