Numerical and Experimental Investigation of a Compressive-Mode Hull Piezoelectric Energy Harvester under Impact Force

In recent years, much research has been carried out to enhance the efficiency of the piezoelectric energy harvester (PEH). This study focuses on the performance of the compressive Hull PEH under impact forces, which simulates real-world scenarios, such as foot strikes or vehicular wheel excitations, more accurately compared to harmonic forces. The experimental results prove the performance of the Hull PEH with less than 5.2% of deviation compared to finite element analysis outcomes under impact forces between 10 N and 1 kN. The Hull PEH more substantially amplified the input force and compressed the piezoelectric material, which was Lead Zirconate Titanate (PZT). Consequently, it amplified the voltage output of a standalone PZT up to 16.9 times under a similar boundary condition. A maximum peak power output of 7.16 W was produced across 50 kΩ of optimum load resistance under 1 kN of impact force, which surpassed the benchmark Cymbal PEH by 37.68 times. Furthermore, it demonstrated a higher energy conversion efficiency of 84.38% under the impact force compared to the harmonic force. This research conclusively proves that the Hull PEH has superior performance in terms of voltage output, power output, loading capacity, and efficiency, making it a promising technology for impact loading applications to generate green energy.