Transformer-Based DC Current Sensor For Digitally Controlled Power Supplies

Abstract

Twenty years ago, R. Severus presented a transformer-based circuit that is able to measure DC currents. However, this circuit did not experience a break-through in the industry or even academic world because it requires too many components and is unable to measure small currents. This paper enhances this circuit so that it becomes feasible to measure currents down to zero. The circuit complexity is no longer an obstacle because in digital controlled power supplies the DSP provides the required auxiliary functionalities. The feasibility of the proposed circuit has been proven by hardware experiment.

Key Words:

• Current sensor
• digital control
• power supplies

Additional information

Notes on contributors

S. Ziegler

Silvio Ziegler received his BE in electrical engineering from Bern University of Applied Sciences, Switzerland, in 2006. In 2006 he was with the company Bachmann Electronic in Feldkirch, Austria, working as a digital design engineer. He is currently pursuing his PhD degree in electrical engineering at The University of Western Australia. His research interests include current sensing techniques, switched mode power converters and digital control techniques.

L.J. Borle

Lawrence J. Borle received his BSc degree from the University of Alberta in 1982, and MSc Degree from the University of Alberta in 1991, both in electrical engineering. He received his PhD degree in electrical engineering (power electronics) from Curtin University of Technology, Perth, in 2000.

From 1982 to 1985, Lawrence was with Chevron Canada Resources Ltd., Calgary, Canada, doing electrical and instrumentation engineering work, and having responsibility for company radio systems engineering. From 1985 to 1988, he worked for Nova Corporation of Alberta in Edmonton, doing electrical and instrumentation engineering work. He returned to University in 1988, studying power electronics. After receiving his MSc in 1991, he worked as a Research Fellow on current-controlled grid-connected inverters in joint venture projects between Curtin University of Technology (CUT) and Advanced Energy Systems Pty. Ltd. (AES), both in Perth, Western Australia. From 1994 to 2000, he was with PowerSearch Ltd., the research and development group of AES, and was leading the commercialisation of current-controlled inverters. In 2000, he became a Lecturer (power electronics) at CUT, and then was a Senior Lecturer in the School of Electrical, Electronic and Computer Engineering at the University of Western Australia from 2002-2007. Since 2007, Lawrence has been working as a Senior Engineer and R&D Leader with SunEnergy Limited In Perth.

H.H.C. Iu

Herbert Ho-Ching Iu received his BEng (Hons) degree in electrical and electronic engineering from the University of Hong Kong, Hong Kong, in 1997. He received his PhD degree from the Hong Kong Polytechnic University, Hong Kong, in 2000.

In 2002, Herbert joined the School of Electrical, Electronic and Computer Engineering, The University of Western Australia, as a Lecturer. In 2007, he became a Senior Lecturer. His research interests include power electronics, renewable energy, non-linear dynamics, current sensing techniques, TCP dynamics and computational intelligence. He has published over 80 papers in these areas. He served as a Visiting Lecturer at the University of Reims Champagne-Ardenne, France, in 2004 and a Visiting Assistant Professor at the Hong Kong Polytechnic University, Hong Kong, in 2006. He currently serves as an Editorial Board Member for the Australian Journal of Electrical and Electronics Engineering, an Editor for the International Journal of Artificial Intelligence, a Guest Editor for Circuits, Systems and Signal Processing, and an Associate Editor for IEEE Circuits and Systems Society Newsletter. He is a co-editor of Chaos Control for Circuits and Systems: A Practical Approach (Singapore: World Scientific, 2008).