A Harmonic Balance Based Stability Domain Analysis of Period-1 Ferroresonance

In an attempt to find regions at risk of ferroresonance, different time domain simulations and analytical approaches were investigated on a one phase laboratory transformer. A 2-D bifurcation diagram based on one-term harmonic balance method has been developed. It was shown increase of core losses during overvoltages, significantly affects the stability domain of period-1 ferroresonance. Time domain simulations show that a static core loss model as a function of the maximum flux of the transformer predicts the second bifurcation point with enough accuracy. This modeling approach was incorporated in harmonic balance analysis. Comparison has been made between analysis and measurements.

Keywords:

Stability domain , ferroresonance , core loss nonlinearity , power transformer