A Comparative Analysis of Multiport DC-DC Converters in Microgrid using Small-Signal Modelling

This paper compares different types of Multiport DC-DC Converters i.e., a Single-Input Single-Output (SISO) Buck-Boost Converter, Single-Input Dual-Output (SIDO) Buck- Boost Converter, Dual-Input Single-Output (DISO) Buck-Boost Converter, Dual-Input Dual-Output (DIDO) Buck-Boost Converter based on different ac modelling approaches to analyze their frequency responses. The basic AC circuit modelling, state-space averaging and converter transfer functions have been derived to figure out how the circuit transfer function and its frequency response complexity increase with the number of ports. It is one of the accurate methods for designing a control scheme based on the AC circuit modelling analysis. The magnitude and phase plot of each transfer function is analyzed to get a brief idea about the Converter operation at particular frequencies indicating resonant poles, RHP zeros or multiple RHP zeros. This analysis can be useful in comprehending the concept and implementation of closed-loop regulation of Multiport DC-DC Converter.