Bifurcation Characterization of Ferroresonance Modes in Power Transformer: Simulation and Experimental Analysis

The occurrence of ferroresonance phenomenon in the electrical network depends on several parameters and situations. To understand this phenomenon, it is necessary to test the occurrence of different ferroresonant modes in transformers. This paper presents a study on the ferroresonance phenomenon, focusing on the characterization of the oscillation modes using bifurcation diagram. Accurate transient models for the transformer using the Tellinen hysteresis model and polynomial approximation are implemented. Bifurcation studies are conducted using numerical simulation and analytical techniques (i.e., Galerkin method). Experimental tests on the transformer are performed using the capacitance values obtained in the bifurcation analysis. Various ferroresonant modes (fundamental, subharmonic, quasi-periodic, and chaotic) are measured. A comparison between the experimental and simulation results validates the elaborated models.