A Stability Analysis Approach of DC Distribution Power System

Th e rapid increase of types of distributed power supply and DC load in DC distribution network makes its weak impedance characteristics obvious, which leads to a series of stability problems such as system voltage fluctuation. At present, there are still few criteria for the stability discrimination of DC distribution network, and most of the existing criteria have high computational complexity and cumbersome discrimination steps. In order to address the above issues, in this paper, a stability analysis strategy for DC distribution network is proposed. Firstly, the stability of each converter circuit is analyzed, and then the DC distribution network is divided into each DC bus subsystem based on impedance interaction, and the stability of the DC distribution network is judged. This strategy can judge the stability of the system step by step from the converter circuit to the DC distribution network, and can reveal the instability source of the system, while considering the impedance interaction of the DCDC converter, the modeling is accurate. Based on this strategy, simulation experiments are designed in Simulink to verify it. The results show that this method can distinguish the instability source of DC distribution network compared with the traditional discrimination method.