The integration of large-scale wind farms will lead to transient stability problems

such as frequency offset

weak feedback and high harmonics

and affect the safe operation of the system. Therefore

research of transient protection technology for large-scale wind farm integration is an urgent requirement. A comprehensive review about grid connection technology and the transient protection technology for large-scale wind farms is carried out. The topology structure of each integration technology is carefully analyzed. Besides

the fault characteristics of three power systems

including permanent magnet synchronous generator

doubly fed induction generator

and traditional synchronous power system are compared and the current research status of transient based protection of onshore and offshore wind farms is illustrated. Finally

perspectives are outlined for future development of relay protection technology in large-scale wind farms

which provides a significant reference for the research of future wind farm integration.