Investigation on the Occurrence of Ferroresonance with the Variation of Core Loss of a Transformer using Nonlinear Dynamic Model of the Transformer

Ferroresonance is a complex electromagnetic phenomenon which has been a problem for power utilities for long time. It can occur in transformers fed through capacitive coupling from various ac power sources. It can be very dangerous, resulting in the generation of sustained overvoltage and overcurrent having magnitudes potentially several times the normal voltage ratings leading to destructive conditions in surge arrester and then transformer in power system. With the advancement of the transformer core materials now a day's transformers are designed and manufactured with very small core loss. The nonlinear dynamic model of the transformer is used. The simulink model developed in MATLAB is examined under various core-loss by varying its core loss resistances to study the ferroresonance. This paper shows that there is much possibility of occurring of ferroresonance by minimizing the core loss in a transformer in the power system.