Doctoral Thesis: Power Electronics Meet Piezoelectrics: Converters, Components, and Miniaturization

Jessica Boles

Abstract:
As converters and controllers of electrical energy, power electronics are the lifeblood of many exciting emerging technologies in transportation, energy systems, manufacturing, healthcare, information technology, and more. However, while integrated circuits have seen miniaturization and expanded performance characterized by Moore’s Law, power electronics often remain the bulkiest, lossiest, and costliest components in the systems they serve. Miniaturization of power electronics is fundamentally bottlenecked by passive components, particularly magnetics (i.e., inductors and transformers), which have long been integral to power conversion but pose inherent size and performance challenges at small scales.

This thesis explores how we can leverage an alternative passive component technology – piezoelectric components – to eliminate magnetics and unlock a new era of miniaturization for power electronics. Piezoelectrics offer numerous size, performance, and manufacturability advantages to power electronics including significantly greater energy densities than magnetics, but harnessing these advantages requires fundamental re-evaluation of both power electronic circuits and piezoelectric components themselves. To this end, I present the following recent advances: (1) Dc-dc converter circuit topologies and control sequences capable of efficiently utilizing piezoelectrics as sole passive components; these converter implementations demonstrate the efficiency viability of piezoelectric-based power electronics and provide their highest experimental efficiencies to date. (2) Piezoelectric component design tools for efficiency and power handling density; this framework enables maximal utilization of piezoelectric components and reveals them to have favorable scaling characteristics to small sizes. (3) An experimental demonstration of dramatic miniaturization offered by piezoelectrics; this prototype piezoelectric component has an order of magnitude lower volume than a competing magnetic component design.

These are important steps in realizing the scalability advantages of piezoelectrics in power electronics, positioning them to revolutionize what is possible for computing, wireless communication, robotics, biomedical devices, renewable energy, and beyond.

Details

• Date: Thursday, June 30
• Time: 1:30 pm
• Location: 4-270

Additional Location Details:

Thesis Supervisor: Prof. David Perreault