Abstract

In a DC distribution system, the strong coupling between multiple converters and busbars often leads to the phenomenon of harmonic resonance interaction, posing a threat to the safe and stable operation of the system. This paper firstly establishes a harmonic impedance model for a double-bus DC system, and then analyses the resonance transmission amplification characteristics through the different interlinking converters, including the isolated DC-DC converter, i.e., Dual active bridge (DAB), and the non-isolated DC-DC converters, i.e., Buck and Boost. Subsequently, a method for optimizing the control parameters of interlinking converters is proposed according to the transmission characteristics of the converters. The proposed method utilizes the hierarchical variable weighting approach to score the impedance matrices under different parameters and identifies the optimal parameters based on the highest scores. The results show that the proposed method provides a guidance for parameter optimization to suppress harmonic resonance transmission and amplification in DC distribution system.