This paper presents a system for vibration and thermal energy harvesting from automobiles, and it intends to power wireless sensor nodes. Two main features of the proposed circuit are impedance matching to extract maximum power and wake-up to incorporate sleep mode. Two separate buck-boost converters in discontinuous conduction mode are used for impedance matching. A wake-up circuit senses the vibration energy generated by a piezoelectric cantilever (PZT). When a car is turned off, the wake-up circuit deactivates the two converters, and the entire circuit goes into sleep mode to save power. The proposed circuit charges a capacitor to power a wireless sensor node, and is able to cold start. The proposed circuit is prototyped with discrete components. Experimental results show that the proposed system harvests peak power of 3.4 mW and these results also demonstrate that a wireless sensor node can be powered by the proposed system.
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A Multi-Source Energy Harvesting System to Power Microcontrollers for Cryptography
This paper presents a multi-source energy harvesting system for vibration, thermal, and solar energy from automobiles, which aims to power a micro controller (MCU) for cryptography. Each building block adopts a maximum power extraction scheme to match the unique characteristic of the energy source. Resistive impedance matching with a buck-boost converter is adopted for vibration and thermal energy harvesting, and maximum power point tracking for solar energy harvesting. The proposed system provides two regulated voltages, 3.3 V and 5 V, to power an MCU. An energy level indicator indicates the current energy level stored in the storage device. The MCU processes a cryptography algorithm accordingly based on the current energy level. The system is able to cold start, i.e., even if the storage device is drained completely, it can start.
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- Award ID(s):
- 1704176
- NSF-PAR ID:
- 10097880
- Date Published:
- Journal Name:
- IECON 2018 - 44th Annual Conference of the IEEE Industrial Electronics Society
- Page Range / eLocation ID:
- 901 to 906
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/IECON.2018.8591833
