The EMC Research On Microcomputer-Based Protective Relays Of UHV Substations

With the development of substation automation and local installation of control device, the electromagnetic environment of substation become more severe than before. First, the typical feature and coupling channel of disturbance source are considered. And then, the prominent problems about uncorrect action of protective relays for disturbance are discussed. Furthermore, the immunity of different ports in protective device has been thoroughly studied in this desertion. Based on analyses and researches above, the experiments on CSL-101B, typical UHV transmission line protection, had been made and the possible methods to solve the problems appeared in these experiments are also proposed in this paper. At the end, in order to solve surge problem, the various earthing modes of system earth in protection device are analyzed. Cao Xiaoguai (Electric Power System and Automation)Directed by prof. Yang Qixun...