Generator Ground Protection Guide

The "Generator Ground Protection Guide" ANSI/IEEE Standard C37.101 has been prepared recently by the Power System Relaying Committee to aid in the application of relays and relaying schemes for the protection of synchronous generators for single-phase-to-ground faults in the stator winding. The various protective schemes along with recommended and alternate methods of protection for the most commonly used generator connections and grounding practices are covered. The purpose. of this paper is to review some of the highlights of the Guide, to familiarize the industry with the scope and usefulness of this new document, and to invite considered discussion for the purpose of improving this guide in the future.