Hybrid Energy Harvesting From Keyboard

Beker, Levent
Zorlu, Ozge
Külah, Haluk
Muhtaroglu, Ali
This paper presents a hybrid energy harvester which combines piezoelectric (PZT) and electromagnetic (EM) transduction mechanisms to scavenge vibration energy from a keyboard. The system comprises of improvements to the dome structure presented in previous studies, in which only PZT transduction mechanism was used to harvest 16.95 mu W of experimentally verified power. An in-house modeling and simulation tool is first introduced in this work to evaluate the integration of EM transduction into the PZT system. The tool combines analytical mechanical equations and FEM results for magnetic fields for the optimization of the electromagnetically generated power. Two designs of different cost are then compared. It is concluded that the design utilizing the frequency-up-conversion technique at an incrementally higher cost is superior due to significantly higher contribution to the generated power compared to the alternative implementation without frequency-up-conversion. Modeling and simulations show an additional 2.81 mu W power can be generated through EM integration to the previous PZT based keyboard energy harvester system.


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Beker, Levent; Külah, Haluk; Muhtaroglu, Ali (2011-12-02)
This paper presents a piezoelectric energy harvester (PEH) to convert vibrations to electrical power. A unimorph cantilever beam is used to generate voltage on piezoelectric material bonded close to the anchor of the cantilever beam. A 4.85 x 1 x 0.04 cm structural layer with piezoelectric material yields peak-to-peak voltage of 64 V at the resonance frequency of the structure. The empirically confirmed maximum power output is close to 0.5 mW. The results from validation data on the observed structure has b...
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Zorlu, Ozge; Turkyilmaz, Serol; Muhtaroglu, Ali; Külah, Haluk (2013-01-24)
This paper presents a MEMS-based electromagnetic (EM) energy harvester for low frequency and low acceleration vibrations. The harvester is an improved version of [1], which operates with the frequency up conversion (FupC) principle. The former structure was composed of a low-frequency diaphragm carrying a magnet and 16 high-frequency cantilevers with coils. In this work, the phase difference between the coil outputs, leading to voltage cancellation in serial connection, has been eliminated by using a single...
An efficient integrated interface electronics for electromagnetic energy harvesting from low voltage sources
Ulusan, Hasan; Gharehbaghi, Kaveh; Zorlu, Ozge; Muhtaroglu, Ali; Külah, Haluk (2013-12-01)
This paper presents a fully-integrated self-powered interface circuit for efficient rectification of the signals generated by vibration based low-voltage electromagnetic (EM) energy harvesters. The circuit utilizes an improved AC/DC doubler structure with active diodes to minimize the forward bias voltage drop for enhancing the rectifier efficiency. The comparators in the active diodes are powered internally by another passive AC/DC doubler with diode connected transistors. The performance is maximized thro...
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This paper presents an electromagnetic (EM) vibrationto-electrical power generator which can efficiently scavenge energy from low-frequency external vibrations. The reported generator up-converts low-frequency environmental vibrations to a much higher frequency through a novel electro-mechanical frequency up-converter using a magnet, and hence provides efficient energy conversion even at low frequencies. Power is generated by means of electromagnetic induction using a magnet and coils on top of resonating c...
Citation Formats
L. Beker, O. Zorlu, H. Külah, and A. Muhtaroglu, “Hybrid Energy Harvesting From Keyboard,” 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/54528.