Modeling and analysis of N-port DC-DC converters

Multi-port DC-DC converters are very attractive because they have the potential to combine different energy sources and management strategies. Their utilization is not only facilitating the entrance of the alternative energy sources into the market but is also reducing the cost and size of conventional energy sources. In this paper, the modeling and analysis of such power electronic devices with N ports are discussed. The derivation procedures of the power flow equations, the large signal model (LSM) and small signal model (state space model) (SSM) are presented. A transformation method to convert the N-windings transformer of the converter from a Star topology to a more suitable modeling topology is also presented. The modeling procedure is demonstrated for a 5-port DC-DC converter. Simulation is then used to compare the LSM and SSM models and observe their performance with respect to a detailed model (DM).