IEC 61850 communications based transmission line protection

IEC 61850 is the new standard for communications in substations that defines a new generation of protection applications based on high speed peer-to-peer communications between different substation devices. Accelerated protection schemes use permissive or blocking signals exchanged between relays at the two or more ends of the protected transmission line in order to provide fast fault clearing for any fault type or location. The paper discusses the different possible implementations of such schemes in substations with IEC 61850 and compares the expected performance of IEC GOOSE based solutions with the conventional hard wired schemes. A directional comparison protection scheme is used as an example. The requirements and methods for testing of such schemes are described at the end of the paper.