With the highly-extensive integration of distributed renewable energy resources (DER) into the grid

the power distribution system has changed greatly in the structure

function and operating characteristics. On this ground

An AC-DC hybrid DER system becomes necessary for effective management and control over DER. This paper first summarizes the physical characteristics and morphological evolution of AC-DC hybrid DER system. The impact of these new features on system configuration planning is analyzed with respect to its flexible networking

rich operation control modes

and tight source-network-load-storage coupling. Then

based on a review of the existing research

problems and technical difficulties are figured out in terms of converter modeling

steady-state analysis

power flow calculation

operating scenarios management

and optimization model solution. In light of the problems and difficulties

a framework for the configuration optimization of AC-DC hybrid DER systems is proposed. At last

the paper provides a prospect of key technologies from six aspects including morphology forecasting

coupling interaction analysis

uncertainty modeling

operation simulation

optimization model solving algorithm and comprehensive scheme evaluation.