Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Circuit transfers four times more power out of shakes and rattle

24.09.2002


Penn State engineers have optimized an energy harvesting circuit so that it transfers four times more electrical power out of vibration – the ordinary shakes and rattles generated by human motion or machine operation.



Using their laboratory prototype, which was developed from off-the-shelf parts, the Penn State researchers can generate 50 milliwatts. Although they haven’t tried it, they believe the motion of a runner could be harnessed to generate enough power to run a portable electronic music device. By comparison, simple, un-optimized energy harvesting circuits, for example the type used to power LEDs on "smart" skis, can only generate a few milliwatts.

The researchers say the new circuit offers an environmentally friendly alternative to disposable batteries for wearable electronic devices or for wireless communication systems. In addition, the circuit could be used in sensor and monitoring networks that manage environmental control in office buildings, robot control and guidance systems for automatic manufacturing, warehouse inventory; integrated patient monitoring, diagnostics, drug administration in hospitals, interactive toys, smart home security systems, and interactive museums.


The new circuit is described in a paper, "Adaptive Piezoelectric Energy Harvesting Circuit for Wireless, Remote Power Supply," published in the September issue of the journal, IEEE Transactions on Power Electronics. The authors are Geffrey K. Ottman, former Penn State master’s degree student; Dr. Heath Hofmann, assistant professor of electrical engineering; Archin C. Bhatt, former Penn State master’s degree student; and Dr. George A. Lesieutre, professor of aerospace engineering and associate director of the Penn State Center for Acoustics and Vibration.

Lesieutre explains that, like other energy harvesting circuits, the new Penn State device depends on the fact that when vibrated so that they bend or flex, piezo-electric materials produce an alternating or AC current and voltage. This electrical power has to be converted to direct current or DC by a rectifier before it can be stored in a battery or used. Hofmann adds that the magnitude of the piezoelectric material’s vibration determines the magnitude of the voltage: "Since, in operation, the amount of vibrations can vary widely, some way must also be found to adaptively maximize power flow as well as convert it from AC to DC."

Using an analytical model, the team derived the theoretical optimal power flow from a rectified piezoelectric device and proposed a circuit that could achieve this power flow. The circuit includes an AC-DC rectifier and a switch-mode DC-DC converter to control the energy flow into the battery.

The Penn State researcher notes that using an approach similar to one used to maximize power from solar cells, the team developed a tracking feature that enables the DC-DC converter to continuously implement the optimal power transfer and optimize the power stored by the battery.

The circuit is the first to include an adaptive DC-DC converter and achieves about 80 percent of the theoretical maximum – well above the operating output of simple energy harvesting circuits.


The research was supported by a contract with the Office of Naval Research

Andrea Elyse Messer | EurekAlert!
Further information:
http://www.psu.edu/

More articles from Power and Electrical Engineering:

nachricht Researchers measure near-perfect performance in low-cost semiconductors
18.03.2019 | Stanford University

nachricht Robot arms with the flexibility of an elephant’s trunk
18.03.2019 | Universität des Saarlandes

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

Im Focus: Sensing shakes

A new way to sense earthquakes could help improve early warning systems

Every year earthquakes worldwide claim hundreds or even thousands of lives. Forewarning allows people to head for safety and a matter of seconds could spell...

Im Focus: A thermo-sensor for magnetic bits

New concept for energy-efficient data processing technology

Scientists of the Department of Physics at the University of Hamburg, Germany, detected the magnetic states of atoms on a surface using only heat. The...

Im Focus: The moiré patterns of three layers change the electronic properties of graphene

Combining an atomically thin graphene and a boron nitride layer at a slightly rotated angle changes their electrical properties. Physicists at the University of Basel have now shown for the first time the combination with a third layer can result in new material properties also in a three-layer sandwich of carbon and boron nitride. This significantly increases the number of potential synthetic materials, report the researchers in the scientific journal Nano Letters.

Last year, researchers in the US caused a big stir when they showed that rotating two stacked graphene layers by a “magical” angle of 1.1 degrees turns...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Researchers measure near-perfect performance in low-cost semiconductors

18.03.2019 | Power and Electrical Engineering

Nanocrystal 'factory' could revolutionize quantum dot manufacturing

18.03.2019 | Materials Sciences

Long-distance quantum information exchange -- success at the nanoscale

18.03.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>