Abstract: The DC microgrid,combined with various forms of ports such as power supply,energy storage,and load,can operate in islanding and grid-connected modes in various situations and is widely used to connect to the AC power grid.Multiple sets of converters are connected in parallel to the DC bus,which will lead to redundancy system,complex control,and low efficiency.By integrating multiple different forms of ports,multi-port DC converters have emerged.This article starts off the presentation with the topology of multi-port converters and the overview of the derivatives of various existing multi-port converters,and then briefly introduces their structures,and analyzes their function,advantages and disadvantages.With the merits of higher reliability and the ability to achieve wide range voltage input and soft switching,the fully isolated multi-port converters,which are independent and sharing a common magnetic bus,has been widely concerned at home and abroad.Due to the coupling of input and output power flow between multiple ports of the converter,it has low efficiency. Three existing decoupling methods applied to multi-port networks were introduced in sequence,and how to decouple them was compared and analyzed based on the corresponding topology. Resonant decoupling achieves physical decoupling by constructing a resonant topology structure,which is relatively simple and effective,with the good performance of transient and steady-state.