Loading Effects on Upstream Converter's Input Impedance in Multistage Dc Power Distribution Systems

This paper investigates the loading effects on the input impedance of the upstream converter stage in multistage dc power distribution systems. The paper shows that the loading effects depend on the topology of the converter stage. The loading effects are not observable in the input impedance of the buck converter. On the other hand, the loading effects are apparent in the input impedances of the boost and buck/boost converters. The outcomes of the paper can be used to analyze the stability of the whole power system. Theoretical results are all validated by both PSpice and PSIM time-domain simulations.