Piezoelectric components are promising alternative passive components for power conversion and have been demonstrated with high power density and efficiency. However, piezoelectric-based dc-dc converters often employ large terminal capacitors to ensure near-constant terminal voltage. In this paper, we model and analyze the effect of finite terminal capacitance on the performance of piezoelectric-based dc-dc converters, and we experimentally verify the modeled efficiency trends. The proposed model will enable piezoelectric-based power converter designers to size terminal capacitances for maximum power density without significant reduction in efficiency.
