摘要
This paper introduces a new complex percentage differential relay for bus protection. It allows greater CT errors during the external fault and is still sensitive to the intemal fault with high fault resistance or out-flowing current.The CTs of the differential circuit of the new relay may have different transformation ratio, so the new relay can share CTs with other relays and don’t need special CTs only for differential protection. It may be applied in transformer differential protection as well.
This paper introduces a new complex percentage differential relay for bus protection. It allows greater CT errors during the external fault and is still sensitive to the intemal fault with high fault resistance or out-flowing current.The CTs of the differential circuit of the new relay may have different transformation ratio, so the new relay can share CTs with other relays and don't need special CTs only for differential protection. It may be applied in transformer differential protection as well.
