Detection of ferroresonance occurrence in inductive voltage transformers through vibration analysis

Steady state ferroresonances in isolated neutral electrical systems result in sustained abnormal system oscillations, which can damage inductive voltage transformers (IVTs) and other system elements. During this phenomenon, the IVT becomes saturated; consequently, the dimensions of the ferromagnetic material of the IVT change owing to magnetostriction. Because of this inherently nonlinear behaviour, the natural vibration modes of the IVT are excited. The aim of this study is to take advantage of these anomalous vibration modes to reveal the occurrence of ferroresonance in IVTs. The methodology for ferroresonance detection in IVTs through vibration analysis is described and demonstrated experimentally.