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Abstract Piezoelectric transducers are widely employed in vibration control and energy harvesting. The effective electro-mechanical coupling of a piezoelectric system is related to the inherent capacitance of the piezoelectric transducer. It is known that passive vibration suppression through piezoelectric LC shunt can be enhanced with the integration of negative capacitance which however requires a power supply. This research focuses on the parametric investigation of a self-sustainable negative capacitance where the piezoelectric transducer is concurrently used in both vibration suppression and energy harvesting through LC shunt. The basic idea is to utilize the energy harvesting functionality of the piezoelectric transducer to aid the usage of negative capacitance in terms of power supply. Specifically, the power consumption and circuitry performance with respect to negative capacitance circuit design is analyzed thoroughly. Indeed, the net power generation is the difference between available power in the shunt circuit and the power consumption of the negative capacitance circuit. There exists complex tradeoffs between net power generation and the vibration suppression performance when we use different resistance values in the negative capacitance circuit. It is demonstrated through correlated analytical simulation and experimental study that the proper selection of the resistance values in the negative capacitance circuit can result in vibration suppression enhancement as well as improved net power generation, leading to a self-sustainable negative capacitance scheme.
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OPTIMIZATION OF A RAINBOW PIEZOELECTRIC ENERGY HARVESTING SYSTEM FOR TIRE MONITORING APPLICATIONS Proceedings of the ASME 2018 12th International Conference on Energy Sustainability ES2018 June 24-28, 2018, Lake Buena Vista, FL, USA ES2018-7496
Ambient energy harvesting using piezoelectric transducers is becoming popular to provide power for small microelectronics devices. The deflection of tires during rotation is an example of the source of energy for electric power generation. This generated power can be used to feed tire selfpowering sensors for bicycles, cars, trucks, and airplanes. The aim of this study is to optimize the energy efficiency of a rainbow shape piezoelectric transducer mounted on the inner layer of a pneumatic tire for providing enough power for microelectronics devices required to monitor tires. For this aim a rainbow shape piezoelectric transducer is adjusted with the tire dimensions and excited based on the car speed and strain. The geometry and load resistance effects of the piezoelectric transducer is optimized using Multiphysics modeling and finite
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- Award ID(s):
- 1650460
- PAR ID:
- 10079086
- Date Published:
- Journal Name:
- Proceedings of the ASME 2018 12th International Conference on Energy Sustainability ES2018 June 24-28, 2018, Lake Buena Vista, FL, USA
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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