Ferroresonance is a phenomenon of complex nature which may be studied profoundly for avoiding it and protect the power equipment with appropriate protective devices when it occurs. The accuracy of the transformer model and the power system’s parameters has a direct effect on the prediction of this phenomenon. A distribution network consists of generators, transformers, capacitors, motors and protective devices may undergo a ferroresonance during some operating situations such as the deenergization of a transformer through a grading capacitor of circuit breaker, a transformer accidentally energized in only one or two phases, or transformer with ongoing phase-to-ground fault. These scenarios are simulated using the data taken from Haoud Berkaoui station in Algeria. A simulation with alternative transients program has been conducted; the obtained results are satisfactory.

Keywords: Distribution power system, Ferroresonance, Power transformer, Grading capacitors, Alternative transient program (ATP) software