A New Class of Topologies for Isolated Piezoelectric-Based Power Conversion

Miniaturization of power converters is limited by the inherently diminished performance of magnetic components at small sizes. Piezoelectric components offer an alternative energy storage mechanism that provides high power density and efficiency, particularly at small sizes. This work extends the development of power converters based on piezoelectric resonators by presenting a novel method for developing isolated dc-dc piezoelectric-resonator-based converters. This class of converters achieves full resonant soft switching and capacitor soft charging without the use of any magnetic components. An example hardware prototype experimentally demonstrates peak efficiencies above 95% for conversion ratios between 0.6 and 0.9. In addition, this design achieves a piezoelectric component power density of 209 W/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>, the highest recorded in an isolated piezoelectric-based topology.