Hybrid Vibration Energy Harvester Based On Piezoelectric and Electromagnetic Transduction Mechanism

Vibration energy harvester converts kinetic energy from ambient vibration into electrical energy. Many energy harvesters in the literature use single element transducer, either piezoelectric, electromagnetic or electrostatic for above purpose. In this paper, a hybrid based energy harvester that integrates with both, piezoelectric and electromagnetic transducers is developed and examined. The energy harvester uses four pole magnets arranged onto a piezoelectric cantilever beam free end, to produce stronger magnetic field over a stationary coil. When the harvester is excited by an external vibration, both piezoelectric and electromagnetic generates electrical energy or power. Experimental results shows that piezoelectric capable to generate optimum power of 2.3mW in a 60k resistive load, while electromagnetic generates 3.5mW power in a 40 resistive load, when vibrated at its resonant frequency 15Hz, and at 1g (1g=9.8ms-2) acceleration. By efficiently integrating both piezoelectric and electromagnetic transducers, more power could be generated as compared to a single transducer over its size

A Hybrid Technique of Energy Harvesting from Mechanical Vibration and Ambient Illumination

Hybrid energy harvesting is a concept applied for improving the performance of the conventional stand-alone energy harvesters. The thesis presents the analytical formulations and characterization of a hybrid energy harvester that incorporates photovoltaic, piezoelectric, electromagnetic, and electrostatic mechanisms. The initial voltage required for electrostatic mechanism is obtained by the photovoltaic technique. Other mechanisms are embedded into a bimorph piezoelectric cantilever beam having a tip magnet and two sets of comb electrodes on two sides of its substructure. All the segments are interconnected by an electric circuit to generate combined output when subjected to vibration and solar illumination. Results for power output have been obtained at resonance frequency using an optimum load resistance. As the power transduced by each of the mechanisms is combined, more power is generated than those obtained by stand-alone mechanisms. The synergistic feature of this research is further promoted by adding fatigue analysis using finite element method

Characterization On Hybrid Circuit For Piezoelectric And Electromagnetic Energy Harvesting From Ambient Vibration Sources

In this research, a series of experimental analyses for the performance of a hybrid energy harvester is carried out in order to produce an optimum electrical output power. The hybrid energy harvester in this research is an integration of piezoelectric and electromagnetic mechanisms. This research is divided into three main stages. In first stage, characterizations of energy harvesters were studied and hybrid energy harvesting topologies using series and parallel connection are proposed. Characterization was based on resonant frequency, acceleration level and output power. It was found that, series topology of piezoelectric and electromagnetic energy harvester at 25 Hz and 0.5 g level is the best topology compared to parallel topology. In the second stage, diode bridge rectifier and active rectifier were designed and simulations were performed to verify with experimental results. Evaluation was based on rectified electrical output from the energy harvester using two topologies. First topology is piezoelectric and electromagnetic energy harvesters connected in hybrid unit was rectified by sharing the same rectifier circuit and second topology is both of energy harvesters were rectified individually. It was found that piezoelectric and electromagnetic rectified individually using active diode performed a higher output power. The last stage is the integration of hybrid energy harvesting system with active rectifier circuit. Piezoelectric and electromagnetic energy harvester was rectified individually using active diode before both energy harvesters were connected in series topology and fed into capacitor. From the experiment result, it was found that hybrid energy harvesting showed significant improvement in overall performance by producing an optimum electrical output power 100 μW derived at resonant frequency of 25Hz with 0.5 g-level from ambient vibration source

Available Technologies and Commercial Devices to Harvest Energy by Human Trampling in Smart Flooring Systems: a Review

Technological innovation has increased the global demand for electrical power and energy. Accordingly, energy harvesting has become a research area of primary interest for the scientific community and companies because it constitutes a sustainable way to collect energy from various sources. In particular, kinetic energy generated from human walking or vehicle movements on smart energy floors represents a promising research topic. This paper aims to analyze the state-of-art of smart energy harvesting floors to determine the best solution to feed a lighting system and charging columns. In particular, the fundamentals of the main harvesting mechanisms applicable in this field (i.e., piezoelectric, electromagnetic, triboelectric, and relative hybrids) are discussed. Moreover, an overview of scientific works related to energy harvesting floors is presented, focusing on the architectures of the developed tiles, the transduction mechanism, and the output performances. Finally, a survey of the commercial energy harvesting floors proposed by companies and startups is reported. From the carried-out analysis, we concluded that the piezoelectric transduction mechanism represents the optimal solution for designing smart energy floors, given their compactness, high efficiency, and absence of moving parts

Simulation of spiral-shaped mems human energy harvester using piezoelectric transduction

Energy harvesters are one of the focus areas in the field of research. The complex smart devices and miniaturized electronic design limit the use of traditional wired power source. The need for an efficient human energy harvester for such devices is growing exponentially every year due to an increase in the demand of energy sources and power requirement for the electronics. In the recent years, the trend of research is leading us to come up with a better solution of replacing the use of non-renewable energy with the renewable sources. Human energy harvesting technique has evolved as an efficient substitute to these. But there are few challenges in designing such energy harvesters. Firstly, obtaining higher efficiency. Moreover, since the efficiency is lower it is difficult to obtain enough energy considered to size. The goal is to model and simulate small scale energy harvester which harvests the ambient energy efficiently. There are several advantages of human energy harvester which make it beneficial, cost-effective and has grabbed the attention of researchers since past several years. In this thesis report, a human energy harvester has been designed in a 2-loop spiral design and simulated to obtain an efficient design using piezoelectric materials.Includes bibliographical reference

Power Processing for Electrostatic Microgenerators

Microgenerators are electro-mechanical devices which harvest energy from local environmental from such sources as light, heat and vibrations. These devices are used to extend the life-time of wireless sensor network nodes. Vibration-based microgenerators for biomedical applications are investigated in this thesis. In order to optimise the microgenerator system design, a combined electro-mechanical system simulation model of the complete system is required. In this work, a simulation toolkit (known as ICES) has been developed utilising SPICE. The objective is to accurately model end-to-end microgenerator systems. Case-study simulations of electromagnetic and electrostatic microgenerator systems are presented to verify the operation of the toolkit models. Custom semiconductor devices, previously designed for microgenerator use, have also been modelled so that system design and optimisation of complete microgenerator can be accomplished. An analytical framework has been developed to estimate the maximum system effectiveness of an electrostatic microgenerator operating in constant-charge and constant-voltage modes. The calculated system effectiveness values are plotted with respect to microgenerator sizes for different input excitations. Trends in effectiveness are identified and discussed in detail. It was found that when the electrostatic transducer is interfaced with power processing circuit, the parasitic elements of the circuit are reducing the energy generation ability of the transducer by sharing the charge during separation of the capacitor plates. Also, found that in constant-voltage mode the electrostatic microgenerator has a better effectiveness over a large operating range than constant-charge devices. The ICES toolkit was used to perform time-domain simulation of a range of operating points and the simulation results provide verification of the analytical results

Review of Contemporary Energy Harvesting Techniques and Their Feasibility in Wireless Geophones

Energy harvesting converts ambient energy to electrical energy providing numerous opportunities to realize wireless sensors. Seismic exploration is a prime avenue to benefit from it as energy harvesting equipped geophones would relieve the burden of cables which account for the biggest chunk of exploration cost and equipment weight. Since numerous energies are abundantly available in seismic fields, these can be harvested to power up geophones. However, due to the random and intermittent nature of the harvested energy, it is important that geophones must be equipped to tap from several energy sources for a stable operation. It may involve some initial installation cost but in the long run, it is cost-effective and beneficial as the sources for energy harvesting are available naturally. Extensive research has been carried out in recent years to harvest energies from various sources. However, there has not been a thorough investigation of utilizing these developments in the seismic context. In this survey, a comprehensive literature review is provided on the research progress in energy harvesting methods suitable for direct adaptation in geophones. Specifically, the focus is on small form factor energy harvesting circuits and systems capable of harvesting energy from wind, sun, vibrations, temperature difference, and radio frequencies. Furthermore, case studies are presented to assess the suitability of the studied energy harvesting methods. Finally, a design of energy harvesting equipped geophone is also proposed

Energy harvesting from human and machine motion for wireless electronic devices

Published versio

Energy Harvesters and Self-powered Sensors for Smart Electronics

This book is a printed edition of the Special Issue “Energy Harvesters and Self-Powered Sensors for Smart Electronics” that was published in Micromachines, which showcases the rapid development of various energy harvesting technologies and novel devices. In the current 5G and Internet of Things (IoT) era, energy demand for numerous and widely distributed IoT nodes has greatly driven the innovation of various energy harvesting technologies, providing key functionalities as energy harvesters (i.e., sustainable power supplies) and/or self-powered sensors for diverse IoT systems. Accordingly, this book includes one editorial and nine research articles to explore different aspects of energy harvesting technologies such as electromagnetic energy harvesters, piezoelectric energy harvesters, and hybrid energy harvesters. The mechanism design, structural optimization, performance improvement, and a wide range of energy harvesting and self-powered monitoring applications have been involved. This book can serve as a guidance for researchers and students who would like to know more about the device design, optimization, and applications of different energy harvesting technologies