Responses in Trasnformers Built with Planar Coils Inner Ring Coils Excited by Square Waves

This paper presents an analysis about the results of experiments using planar coils inner ring coils to determine a transformer. The excitation of this system was a square wave voltage, where experiments were realized in two ways: considering planar coil as primary and observing responses on secondary being ring coil (direct system) and the inverse (ring coil as primary and planar coil as secondary-inverted system). In this study, a phenomenon not common in literature on system response is analyzed, showing efiects of changes on transfer function in both cases when varying turn numbers of each coil and several variations on responses due to changes on resistances, parasitic capacitances, self and mutual inductances of the coils. The uncommon phenomenon appears as modulated response on speciflc turn ratio. The obtained results can be used to researches in areas as power electronics and pulse transformers.