The ferroresonance phenomena in electrical power systems can cause very important quality and security problems. Although it has been extensively analyzed with different approaches since the birth of electrical systems, it still remains a challenge due the complexity of factors that can lead to the phenomenon. In this paper, a scalar Jiles-Atherton (JA) hysteresis model is applied to model a nonlinear ferromagnetic core allowing to analyze magnetic circuits, which can be in ferroresonant mode. It is used an inverse JA approach, which had originally the magnetic induction as its independent variable. The analysis here proposed applies a flux-current methodology to obtain a hysteresis behavior of a nonlinear inductor.