By Prof. Saad Mekhilef, University of Malaya, Kuala Lumpur, Malaysia.
University of Malaya
Kuala Lumpur, Malaysia.
Abstract:
Uninterruptible Power Supplies (UPS) are widely used to provide reliable and high quality power to critical loads such as such as airlines computers, datacenters, communication systems, and medical support systems in hospitals in all grid conditions. Online UPS system is considered to be the most preferable UPS due to its highest level of power quality and proven reliability against all types of line disturbances and power outages. This paper presents a new topology of the non-isolated online uninterruptible power supply system. The proposed system consists of bridgeless boost rectifier, battery charger/discharger, and an inverter. The rectifier performs power factor correction and provides regulated DC-link voltage. The rectifier operates with a minimum semiconductor device, reducing the conduction losses of the circuit significantly. A new battery charger/discharger has been implemented, which ensures the bidirectional power flow between the DC-link and the battery bank, reducing the battery bank voltage to only 24V, and regulates the DC-link voltage during battery mode. The proposed controller shows significant improvement in terms of reducing the total harmonics distortion to 0.5% for linear load and 1.25% for non-linear load, strong robustness, and fast response time of only 0.3ms. Operation principle and experimental results of 1kVA prototype have been presented to verify the validity of the proposed UPS. The efficiency of the proposed system is 94% during battery mode and 92% during the normal mode of operation.
Biography
“Professor Dr. Saad Mekhilef is a Charted Engineer (CEng) and Fellow of The Institution of Engineering and Technology (IET), and a Senior Member of The Institute of Electrical and Electronics Engineers (IEEE). He is an Associate Editor of various top journals such as IEEE Transactions on Power Electronics and the Journal of Power Electronics. He is a distinguished Professor at Swinburne University of Technology, Melbourne, Australia and also an Honorary Professor at the Department of Electrical, Faculty of Engineering, University of Malaya, Malaysia. He is the Director of Power Electronics and Renewable Energy Research Laboratory (PEARL). He authored and co-authored for more than 400 publications in academic journals and proceedings and five books with more than 30,000 citations. He is frequently invited as honorary keynote lectures at international conferences, congress, meetings, and symposiums.
Saad Mekhilef has been listed by the Thomson Reuters (Clarivate Analytics) as one of the Highly Cited (Hi.Ci) engineering researchers in the world, and included in the “Thomson Reuters’ The World’s Most Influential Scientific Minds: 2018, 2019 and 2020”. He is actively involved in industrial consultancy for major corporations in the Power Electronics and Renewable Energy projects. His research interests include Power Conversion Techniques, Control of Power Converters, Maximum Power Point Tracking (MPPT), Renewable Energy, Energy Efficiency, Smart Grid, Microwave and Wireless Technologies.
More Information about my research can be found at
1. http://scholar.google.com
2. https://umexpert.um.edu.my/saad.html
3. http://pearl.um.edu.my/
4. http://www.researcherid.com/rid/B-9652-2010
5. http://www.scopus.com/authid/detail.url?authorId=6603317449