Piezoelectric energy harvesting experiments under combined aerodynamic and base excitation

Abstract

The behavior of film-type piezoelectric energy harvesters under simultaneous aerodynamic and base excitation was experimentally investigated. Two flutter type piezoelectric film transducers (LDT0-028K and LDT1-028K) were excited with the 31 excitation mode. The aerodynamic excitation was produced by a centrifugal fan. The base excitation was produced by a cone speaker driven by sinusoidal voltage waveforms in the frequency range of 20 to 250 Hz. This frequency range includes the two transducers’ resonant frequencies. The voltage output of the harvesters was monitored by an oscilloscope and the base excitation was monitored with acceleration measurements. The measured output voltage signals were analyzed by Fast Fourier Transformation. The tip deflection of the piezo-films was monitored with long exposure photography. Harvesting power output was estimated by simple calculations. The results are discussed aiming to support the optimal design of vibration energy harvesting layouts with piezoelectric transducers. To this end, information was extracted about the exploitable bandwidth of piezoelectric films.