Dr Geoff V. Merrett
| | | | | |

Two Papers Accepted for Publication in IEEE Transactions

26th September 2011

Our paper on supercapacitor modelling
Our paper on supercapacitor modelling
We have recently had two papers related to our work on Energy Harvesting electronics accepted for publication in the IEEE Transactions on Circuits and Systems. Both publications are a result of the EPSRC project on 'Holistic Energy Harvesting'.

The first paper, 'Accurate Supercapacitor Modeling for Energy-Harvesting Wireless Sensor Nodes' investigates supercapacitors, often used in energy-harvesting wireless sensor nodes (EH-WSNs) to store harvested energy. Until now, research into the use of supercapacitors in EH-WSNs has considered them to be ideal or over-simplified, with non-ideal behavior attributed to substantial leakage currents. In this brief, we show that observations previously attributed to leakage are predominantly due to redistribution of charge inside the supercapacitor. We confirm this hypothesis through the development of a circuit-based model which accurately represents non-ideal behavior. The model correlates well with practical validations representing the operation of an EH-WSN, and allows behavior to be simulated over long periods..

The second paper, 'Photovoltaic Sample-and-Hold Circuit Enabling MPPT Indoors for Low-Power Systems' presents an ultra low-power maximum power point tracking (MPPT) circuit with a novel sample-and-hold and cold-start arrangement, enabling efficient indoor MPPT (which has not been reported, or considered possible, before). The circuit is validated in practice, and the sample-and-hold behaviour analysed using real light data.

For more information, click here.

Other Articles

Research Featured in New Scientist
12th September 2013
New Scientist Issue 2932
Our research into the use of smartphones to for biodiversity monitoring has been featured in New Scientist. The New Forest Cicada is the only cicada native to the UK and, having not been seen for many years, is at great danger of becoming extinct. One of my PhD students, Davide Zilli, is investigating whether or not the millions of annual visitors to the New Forest National Park can be turned into mobile biodiversity sensors, using the smartphones that they carry with them. "Biologists lik... [more]

Research Fellow wanted in Networked Embedded Systems
8th May 2017
Networked Embedded Systems Research Fellow
I am recruiting for a Research Fellow for a multidisciplinary project researching wearable, self-powered, embedded sensing systems that are wirelessly networked with smart city infrastructure. This particular post is related to the project's Circuits and Algorithms theme, which is concerned with novel circuits, algorithms and protocols to enable the efficient integration of energy harvesting sources into low-power networked sensing systems. The successful applicants will research, develop and ev... [more]

a GM webdesign This page was last updated on 13th June 2013, and has been successfully validated as HTML 4.0 Transitional and CSS level 2.1
Website tested with Internet Explorer 7, Mozilla Firefox 3, Apple Safari 3, Google Chrome 1 and Opera 9.
For comments and suggestions on, please email webmaster@geoffmerrett.co.uk.

© Geoff Merrett 2017