Orthogonal Piezoelectric Energy Harvester for Low Frequency Applications: Modeling and Experimental Validation 
N H H A Talib1, H Salleh2, M J Brennan3
1N H H A Talib, Institute of Sustainable Energy, Universiti Tenaga Nasional, 43000 Selangor, Malaysia
2H Salleh, Institute of Sustainable Energy, Universiti Tenaga Nasional, 43000 Selangor, Malaysia
3M J Brennan, Department of Mechanical Engineering, São Paulo State University (UNESP), 01049-010 São Paulo, Brazil.
Manuscript received on November 12, 2019. | Revised Manuscript received on November 25, 2019. | Manuscript published on 30 November, 2019. | PP: 6268-6274 | Volume-8 Issue-4, November 2019. | Retrieval Number: D5106118419/2019©BEIESP | DOI: 10.35940/ijrte.D5106.118419
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© The Authors. Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC-BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Abstract: The use of piezoelectric energy harvesters in low frequency applications is a classic problem due to the high elastic modulus of currently available piezoelectric materials. Furthermore, the output power is proportional to the third power of the excitation frequency. Higher excitation amplitudes or an increase in the piezoelectric material can produce a high output power. However, this is not feasible for weak environmental vibration, and using more piezoelectric material would incur a higher cost so this is not an attractive option. This article proposes an L-shaped piezoelectric energy harvester that amplifies the excitation amplitude with the aid of an extension arm. The effects of bending and rotational inertia are considered when modelling the open-circuit voltage that can be generated by the harvester. Experimental validation is carried out using zinc, aluminium and galvanized steel extension arms. The prediction model provides a good estimation of the results with acceptable error percentages for linear elastic extension arms. It is found that the proposed harvester geometry generates more output voltage for all lengths of extension arm, and the optimum lengths are different for each material. The use of a zinc extension arm generated 290 μW at 49 Hz, which is 55% greater than the power generated by a harvester without an extension arm that had a power density of 1.41 μW/mm3.
Keywords: Piezoelectric Energy Harvesters, High Output Power Zinc, Aluminium, Galvanized Steel.
Scope of the Article: Data Modelling, Mining and Data Analytics.