Impedance matching for broadband piezoelectric energy harvesting

13th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications

物理学;能源学

Hagedorn, F.^1 ; Leicht, J.^1 ; Sanchez, D.^1 ; Hehn, T.^2 ; Manoli, Y.^1,2

Fritz Huettinger Department of Microelectronics, Department of Microsystems Engineering-IMTEK, University of Freiburg, Germany^1

HSG-IMIT-Institute of Micromachining and Information Technology, Villingen-Schwenningen, Germany^2

关键词: Capacitive switching;    Discrete components;    Numerical parameters;    Optimization algorithms;    Piezoelectric energy harvesting;    Piezoelectric harvester;    Reference currents;    Resonance frequencies;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/476/1/012083/pdf
DOI  :  10.1088/1742-6596/476/1/012083

来源: IOP

【 摘 要 】

This paper presents a system design for broadband piezoelectric energy harvesting by means of impedance matching. An inductive load impedance is emulated by controlling the output current of the piezoelectric harvester with a bipolar boost converter. The reference current is derived from the low pass filtered voltage measured at the harvester terminals. In order to maximize the harvested power especially for nonresonant frequencies the filter parameters are adjusted by a simple optimization algorithm. However the amount of harvested power is limited by the efficiency of the bipolar boost converter. Therefore an additional switch in the bipolar boost converter is proposed to reduce the capacitive switching losses. The proposed system is simulated using numerical parameters of available discrete components. Using the additional switch, the harvested power is increased by 20%. The proposed system constantly harvests 80% of the theoretically available power over frequency. The usable frequency range of ±4Hz around the resonance frequency of the piezoelectric harvester is mainly limited due to the boost converter topology. This comparison does not include the power dissipation of the control circuit.