Piezoelectric Transformers in Power Electronics: Principle, modeling and measurement techniques

Power electronic circuits have traditionally been based on magnetic technology, and until recently, have not been part of the tide of miniaturization and integration advances from which signal- processing integrated circuits have benefited. In an effort to miniaturize power components piezoelectric, rather than magnetic transformer could be employed in the power supplies. Utilization of piezoelectric transformers in power electronics became possible since new piezoelectric materials have recently been grandly developed that exhibit improved piezoelectric ceramic characteristics. In the past few decades, piezoelectric transformers have been developed and used widely in many applications, such as DC/DC converters, adapters, and electronic ballasts for fluorescent lamps. The unique nature of the piezoelectric transformer offers the opportunity for innovative circuit design such as operating above resonance for inductive behavior to achieve soft switching without compensating inductors.