The safe and stable operation of converter station valve hall equipment is of great significance to the power system. This paper systematically reviews the research progress in state monitoring and intelligent operation and maintenance (O&M) technologies for key equipment

addressing the concealed fault issues that may arise during the long-term service of valve hall equipment. First

this paper examines the structural characteristics

typical fault modes

and current mainstream monitoring methods of three core facilities

namely

converter valves

valve-side bushings

and key auxiliary equipment. Second

based on the fault mechanism analysis of typical hidden hazards

this paper summarizes advanced sensing and diagnostic methods for fault features such as partial discharge

abnormal overheating

structural loosening

and damage. Next

this paper highlights the application potentials of cutting-edge technologies

such as digital twins and artificial intelligence

in constructing intelligent O&M systems. Finally

this paper provides an outlook on the future development directions of intelligent O&M systems for converter station valve halls. The research in this paper offers a systematic reference and methodological support for improving valve hall state perception accuracy

refining fault mechanism modeling

and promoting the intelligentization of O&M systems.