IEEE C37.109:2023

Revision Standard - Active.
A guide to the methods and configurations for the protection of power system shunt reactors is provided in this guide. The protection of oil-immersed reactors equipped with auxiliary power windings, improved turn-to-turn fault protection, and use of digital (microprocessor-based) protection for shunt reactors are included.

This guide includes descriptions of acceptable protective relay practices applied to power system shunt reactors. The guide covers protection for dry-type air-core and oil-immersed-type reactors connected to power system buses and lines. Also included in this guide is the protection of oil-immersed reactors equipped with auxiliary power windings.
The purpose of this guide is to provide users of shunt reactors acceptable methods and configurations for the protection of power system shunt reactors.