FAULT PROTECTION SYSTEM FOR POWER SUPPLIES THAT USE FERRO-RESONANT TRANSFORMERS

摘要

A fault detection system for use in power supply systems using ferro-resonant transformers is presented. A current transformer (17), magnetically coupled to the ferro-resonant circuit (18) of the ferro-resonant transformer (19) is used to sense the current flowing in the ferro-resonant circuit. A fault detection circuit (20), powered by its own power supply (32) connected to the primary source of power (8), monitors the sensed current and signals any significant change therein. A fault condition in any of the secondary circuits of the transformer causes the ferro-resonant current to change, and upon sensing this change, the fault detection circuit disconnects the primary of the transformer from the source of power.