Modelling and analysis of a piezoelectric unimorph cantilever for energy harvesting application

ABSTRACT

Piezoelectric energy generator with an unimorph cantilever working in 31-mode can convert external mechanical stimuli into electrical energy. Its potential application includes wireless sensor network and integrated electronic devices. In this work, an unimorph cantilever subjected to an external mechanical excitation is discussed. Analytical expressions relating generated electric charge, the open voltage and generated energy to the applied mechanical excitation are derived based on the constitutive equations of piezoelectric material. The dependence of charge, voltage and energy sensitivities on elastic modulus ratio and thickness ratio of the elastic substrate and piezoelectric layer under different conditions are also examined. The primary focus of this work is to investigate some geometrical parameters in order to improve the generated energy of the desired piezoelectric energy harvester by developing a model. Such model is also in a good agreement with the experiment results.

KEYWORDS:

• Piezoelectric unimorph cantilever
• elastic modulus ratio
• thickness ratio
• energy harvesting

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The research was supported by the National Natural Science Foundation of China [NSFC No. 51902094] and the Nature Science Foundation of Hubei Province [ZRMS2019001790].