HARDENING NONLINEAR STIFFNESS BEHAVIOUR OF PIEZOELECTRIC MATERIALS WITH PASSIVE NONLINEAR P-N JUNCTION CAPACITANCE SHUNT CIRCUITS

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2021-9-06
Taşkıran, Muhammed Ali
Piezoelectric materials are electromechanical energy transducers. They can be utilized actively when energized electrically or passively when connected to a passive shunt circuit. Due to this, they have been suggested for several vibrations suppression and energy harvesting applications. In this thesis, a novel way to attain passive hardening stiffness was suggested by introducing an electrical component for passive nonlinear piezoelectric vibration isolation or energy harvesting. Since piezoelectric materials can be used actively or passively, the introduced component allows it to use of active and passive vibration isolation techniques at the same time. A passive nonlinear component was suggested to be hardening capacitor attained by P-N junction. For the first step of this thesis, conceptual proof that hardening capacitor provides hardening stiffness is demonstrated. The hardening effect in frequency and time domain for single degree of freedom is then studied as the next step. Then the study is extended to piezo attached cantilever beam case. Equations for the beam structure are derived, and they are validated with numerical solutions and tests. It is shown that the test and the numerical simulation results are in agreement with the analytical solutions.

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Citation Formats
M. A. Taşkıran, “HARDENING NONLINEAR STIFFNESS BEHAVIOUR OF PIEZOELECTRIC MATERIALS WITH PASSIVE NONLINEAR P-N JUNCTION CAPACITANCE SHUNT CIRCUITS,” M.S. - Master of Science, Middle East Technical University, 2021.