The use of piezoelectric cantilever (fixed-free) beam configurations is a widely adopted strategy for harvesting electrical power from ambient mechanical vibrations. This study introduces a theoretical model of a piezoelectric vibration energy harvester integrated with a shape memory alloy (SMA) layer, designed to actively regulate the system’s natural frequency and enhance energy conversion performance. The SMA element plays a crucial role in adjusting the resonant characteristics of the composite beam. The proposed design includes a tapered piezoelectric (PZT) layer, a supporting substrate, and an SMA sheet. Based on classical beam theory, the governing equations are formulated to describe the system’s dynamic response in terms of voltage generation, current flow, and power output, incorporating the thermal effects that influence overall efficiency. Results indicate that incorporating a tapered PZT layer leads to increased power output. The study reveals that natural frequency tuning ranges from 26% to 36% for the vibration modes in short-circuit and open-circuit terms. This strategy connects a vital link between dormant energy collection and intelligent responsive frameworks, presenting a conceptually solid technique for crafting self-adjusting harvesters tailored for settings with varying vibration patterns. The SMA-integrated tapered PZT harvesters can be implemented in self-sustained medical implants, aerospace platforms, and Internet of Things sensors requiring dependable energy harvesting under varying vibration conditions.
Shwetha et al. (Wed,) studied this question.