The development and perspective of relay protection technology

The paper introduces the development of relay protection technology in recent years, exemplifies the several stages of relay protection and characteristics by combining electric power technology and renewable energy development. The new development of relay protection technologies are presented, such as fault component based on novel protection algorithm, adaptive relay protection, travelling wave protection, transient component based relay, applications of parameter identification and artificial intelligence technology in protections. And the immature reasons of the artificial intelligence technology application in protections are also analyzed. Finally the development trend of relay protection is indicated.