In context of the emerging energy internet

the energy router (ER) is one of the core components of multi-port energy conversion and active energy flow regulation. In this paper

ER is classified into three categories based on its functional characteristics: electrical ER

information ER

and multi-energy ER. Based on the differences between the categories

this paper divides the research on ER into four aspects: power conversion

which focuses on multi-port power conversion; energy routing

which is concerned with the optimization of power flow between ports; information processing and optimal control

which is characterized by an emphasis on intelligence

the coupling of information and energy flow; multi-energy

which has the comprehensive utilization of multiple energies as its main objective. Building on these four research aspects

this paper explores the topologies

control strategies

and optimization methods of ER and related techniques. It compensates for the limitation in coverage due to existing research focusing only on specific application scenarios. This paper also explores the potential of ER to promote the economic and stable operation of power grids. Finally

an outlook is provided on the prospective roles and applications of ER in next-generation energy systems.