Investigation on the Stability of an Electric Power Circuit under Ferroresonance Based on Nonlinear Dynamic Model of Transformer

Background: Ferroresonance is a complex electrical phenomenon, which has long been considered a problem for power utilities. Besides, founding mitigation techniques, researchers have also devoted their efforts to predicting the occurrence of ferroresonance in susceptible networks. The study requires mathematically suitable transformer models for computer simulations. Objective: The objective of this paper is to study ferroresonance and examine the stability of the system when source voltage changes gradually from a low value to a high value. Methods: To meet the objective, the first thing required is to find an appropriate circuit model. The saturable core transformer is represented by its nonlinear dynamic model. With the help of that model, a Simulink block diagram has been developed in MATLAB. The Simulink model is examined under various circuit conditions and the stability of the system is analyzed at different stages. Results: It has been found that the system passes through a series of period-doubling bifurcation and ultimately reaches chaos. Conclusion: The model and the method used in this paper can be used as a very helpful tool as well as a powerful technique to understand the effect of specific parameters in the final behavior of the ferroresonance phenomenon.