IEEE PC57.107 PDF

IEEE PC57.107 PDF

This recommended practice describes procedures for developing design-specific operational limits for liquid-immersed power transformers that are connected to generators or power systems that are subjected to significant short duration increases in the core excitation caused by significant changes in the voltage and/or frequency levels.
The purpose of this recommended practice is to provide procedures for developing design-specific V/Hz vs. time curves for use by manufacturers of power transformers. These curves provide recommended operating limits for different types of transformers, different designs and different insulation materials used in those power transformers. Such more accurate and more design-specific V/Hz curves aid users in the proper design and settings of protective relay protection systems for power transformers.
New IEEE Standard – Active – Draft. This document provides the recommended process and criteria for developing V/Hz curves for relay protection purposes for power transformers directly connected to generators