This paper presents a piezoelectric energy harvester using an eccentric cylinder undergoing bending–torsion vibration in low-speed water. It can harvest energy from water using vortex-induced vibration (VIV). A distributed parameter beam model with respect to the motion of the piezoelectric beam was established based on Euler–Bernoulli beam theory. The governing coupled equations of the harvest...

This paper focuses on improving the energy conversion process for low-voltage energy harvester powered wireless sensors by optimising the conversion stages for pulsed sensor operation. The proposed circuit has been designed to operate efficiently with both a low-voltage low-power energy harvester source and a low-power pulsed load. This ensures that continuous conversion losses are kept to a mi...

This paper introduces the basics of energy harvesters and demonstrates two specific vibratory-type energy harvesters developed at the University of Hyogo. The fabrication and evaluation results of the vibratory-type energy harvesters, which employ electrostatic and electromagnetic mechanisms, are described. The aim of developing these devices is to realize a power source for an autonomous human...

Here, we report a stable and predictable aero-elastic motion in the flow-driven energy harvester, which is different from flapping and vortex-induced-vibration (VIV). A unified theoretical frame work that describes the flutter phenomenon observed in both "stiff" and "flexible" materials for flow driven energy harvester was presented in this work. We prove flutter in both types of materials is t...

An idling scheme of Synchronous Switch Harvesting on Inductor (SSHI) is proposed for piling up output voltage of the piezoelectric energy (PE) harvester cycle by cycle, to deal with the PE harvester’s low output voltage. The proposed rectifier integrates active diodes and a parallel-SSHI technique with a simple control scheme, and therefore has a high efficiency. The simulation results demonstr...

This paper presents the design and evaluation of a novel permanent magnet (PM) energy harvesting system for scavenging electrical energy from ambient vibrations. A two-phase tubular linear PM vibration energy harvester consisting of a mover attached with permanent magnets and a slotted stator with built-in two-phase electromagnetic coils is proposed to convert vibrational kinetic energy into el...

The objective of this paper is to study the effect of the internal transducer resistance on the dynamic behaviour and the output power of an energy harvester when it is attached to a cubic load resistance. It is seen that by considering the internal resistance, the dynamic equation of a conventional nonlinear energy harvester changes so that it is not easy to separate the linear damping from th...

Human motion energy harvesting as an alternative to battery powering in body worn and implanted devices is challenging during prolonged periods of inactivity. Even a buffer energy storage system will run out of power eventually if there is no external acceleration to the harvester. This paper presents a method to actuate the rotor inside a previously presented rotational piezoelectric energy ha...

Energy harvesting is attractive for powering wireless sensors, especially in applications such as body sensor networks and pervasive sensing, where power source replacement or recharging is impractical. A MEMS (micro-electro-mechanical systems) electrostatic harvesting device suitable for body motion has been reported previously, using a rolling rod as the proof mass. A new rolling rod device i...