Piezoelectric Transformer Component Design for DC-DC Power Conversion

Abstract

Piezoelectric transformers (PTs) are a promising energy storage alternative to magnetics for power converter miniaturization. PTs offer galvanic isolation and voltage transformation like traditional magnetic transformers, but with superior power scaling properties at small size scales. Despite these advantages, most magnetic-less PT-based dc-dc converter designs have limited efficiencies and power densities. In this paper, we present a design framework for PTs that enables high efficiency and energy handling density at a nominal operating point, while maintaining high-efficiency converter behaviors such as zero voltage switching (ZVS). We illustrate this design process in the context of dc-dc power conversion, and the result suggests that significant gains in PT performance are possible with existing materials using these design strategies.