prDS IEC TR 61850-90-21:2025 ED1:2026

Communication networks and systems for power utility automation - Part 90-21: Travelling Wave Fault Location

Scope

IEC TR 61850-90-21:2025, which is a Technical Report, aims to provide background information, use cases, data models and guidance on the application of such a technique.
This document will
1) describe the principles of fault location based on travelling waves aided by communications;
2) specify use cases for this method under the following application scenarios:
a) Single-ended fault location,
b) Double-ended fault location through communications between two devices,
c) Double-ended fault location with communications to a master station,
d) Wide area fault location applications,
e) Pulse radar echo method,
f) Substation integration with other fault location and disturbance recording functions,
g) Testing and calibration;
3) describe the information model for each use case;
4) give guidance on scheme configuration.