Methods and configurations of lc combined transformers and effective utilizations of cores therein

Abstract

The LC combined transformer is a combination of capacitors, inductors and an electrically-isolated mutual inductor, i.e. conventional transformer; which in principle is a unity-coupled mutual capacitor or a cascade connection of an ideal transformer and unity-coupled mutual capacitor(s). To improve the imperfections of widely-used transformers, by employing the simplest passive-circuit design to attain a perfectly-functional match between mutual capacitors and the mutual inductor, this invention achieves optimal features of current or/and voltage transformation, and introduces a new function of waveform conversion from square to quasi-sine. The ideal current transformer herein is suitable for sinusoidal current measurements, the ideal voltage transformer herein suitable for sinusoidal voltage measurements, and they also could be upgraded to ideal transformers for both current and voltage transformations. This transformer can be designed as power transferable as well as waveform convertible, applicable in power systems or power electronics. Herein also states the design approach of integrated inductor and mutual inductor, and the use of push-pull inductor, materials being fully utilized and sizes decreased.