Powering-up Wireless Sensor Nodes Utilizing Rechargeable Batteries and an Electromagnetic Vibration Energy Harvesting System

• Main Authors: Salar Chamanian, Sajjad Baghaee, Hasan Ulusan, Özge Zorlu, Haluk Külah, Elif Uysal-Biyikoglu
• Format: Article
• Language: English
• Published: MDPI AG 2014-10-01
• Series: Energies
• Subjects: autonomous wireless sensor node; MicaZ; energy harvesting; electromagnetic energy harvester; rechargeable battery
• Online Access: http://www.mdpi.com/1996-1073/7/10/6323

This paper presents a wireless sensor node (WSN) system where an electromagnetic (EM) energy harvester is utilized for charging its rechargeable batteries while the system is operational. The capability and the performance of an in-house low-frequency EM energy harvester for charging rechargeable NiMH batteries were experimentally verified in comparison to a regular battery charger. Furthermore, the power consumption of MicaZ motes, used as the WSN, was evaluated in detail for different operation conditions. The battery voltage and current were experimentally monitored during the operation of the MicaZ sensor node equipped with the EM vibration energy harvester. A compact (24.5 cm3) in-house EM energy harvester provides approximately 65 µA charging current to the batteries when excited by 0.4 g acceleration at 7.4 Hz. It has been shown that the current demand of the MicaZ mote can be compensated for by the energy harvester for a specific low-power operation scenario, with more than a 10-fold increase in the battery lifetime. The presented results demonstrate the autonomous operation of the WSN, with the utilization of a vibration-based energy harvester.