Comparative Performance Characteristics of Current Transformers and Rogowski Coils used for Protective Relaying Purposes

This paper compares performance characteristics of conventional current transformers and Rogowski coils used for protective relaying purposes. Rogowski coils have low-power outputs. They are linear (do not saturate like conventional iron- core current transformers), are compact in size, and light in weight. This paper describes current technology and application for Rogowski coils, which serve in the role of current transformers for measuring power system currents for protective relaying or other measurement purposes. A forthcoming guide PC37.235 from the IEEE PSRC will give detailed information and help for users.