A Gallium Nitride Based High Bandwidth, Extended Single-Ended Primary Inductance Converter, for Fast Balancing of Ultracapacitors

Abstract

Ultracapacitors (UCs) are the preferred choice for specific power requirements. Series and parallel of UCs are required to match the required voltage and power, as the available voltage range is 2.5 to 3 VDC. Passive and active balancing is inevitable here, while some demand, high bandwidth control for fast balancing and stable operations. A novel Extended-Single Ended Primary Inductance Converter (E-SEPIC) is used to actively balance the UCs. A new, simple and effective method is formulated to achieve a higher Degree of Balancing of UCs. A two-stage E-SEPIC with Silicon (Si) and Gallium Nitride (GaN) switch based are demonstrated with an input of 12 VDC to balance up to 3 VDC UCs at the output for high bandwidth and high-power density properties. An effective method of emulating impedance of UCs using Hybrid Electro-chemical Impedance Spectroscopy is evolved. The devised novel method of balancing is effective in height of balancing with GaN based converter exhibiting higher bandwidth of around 30 kHz around 18 times better, with increased efficiency of 12% with an improved power-density of 8.25 times in comparison with that of Si based. This contribution of GaN properties in electrical performance enhancements has influenced the design of Power Electronics applications.

Keywords:

• GaN - Gallium nitride
• HEMT - High electron mobility transistor
• SEPIC - Single-Ended Primary-Inductance converter
• HBD - High Band-Width
• HPD - high power density
• HF - high frequency
• UC - Ultracapacitor

Acknowledgments

The authors thank Miss. Neeraja K and Mrs. Bhavya Y V at C-DAC, Thiruvananthapuram for the test and measurement support.

Disclosure statement

No potential conflict of interest was reported by the author(s).

AUTHORS’ CONTRIBUTION

The authors declare that there is an equal contribution of work of the three in the design and implementation of the work that is projected in this paper.

Additional information

Funding

The work is supported by the Ministry of Science and Technology, Department of Science and Technology, Govt. of India, through the Advanced Manufacturing Technology (AMT) program of Technology Development and Transfer (TDT) department vide order DST/TDT/AMT/2017/123/G & and C dated 12^th September 2018.

Notes on contributors

Chandrasekar Venkatesan

Chandrasekar Venkatesan (SM’16) received the B.E (EEE) degree from Coimbatore Institute of Technology, Coimbatore, India, in 1995 and the M.E in Power Electronics and Drives from College of Engineering, Anna University, Chennai, India, in 1997. Subsequently, he joined C-DAC(T) in Power electronics group, where he is currently a Scientist ‘G’/Sr. Director. He is currently pursuing his Ph.D. degree at NIT Tiruchirappalli. His areas of interest are switch-mode power converters for Automotive (EV and HEV) and Industrial applications, Power conditioners for Fuel cell and other renewable power plants, WBG (SiC & GaN) devices-based Power Electronics.

Chilakapati Nagamani

Chilakapati Nagamani (SM’15) received the B.Tech. degree from S.V.U.C.E., Tiruapati, M.Tech. degree from IIT, Kanpur, and the Ph.D. degree from the University of Technology, Sydney, NSW, Australia, respectively. From 1985 to 1991, she was with the Central Power Research Institute, Bangalore, India. Subsequently, she joined the EEE Department, National Institute of Technology (then known as Regional Engineering College), Tiruchirappalli, India, as a lecturer. Currently, she is a Professor (HAG) with the same department. Her research interests include power electronics and drives, renewable energy systems, WBG power Electronics and FACTS controllers.

Saravana Ilango Ganesan

Saravana Ilango Ganesan (SM’17) graduated from Madras University, Chennai, India, in 2000. He received the M.E degree from Bharathidasan University, Tiruchirappalli, India, in 2001, and the Ph.D. degree from National Institute of Technology, Tiruchirappalli. From 2001 to 2004, he was a Lecturer with Noorul Islam College of Engineering, Kumaracoil, India. Currently, he is an Professor with the Department of Electrical and Electronics Engineering, National Institute of Technology, Tiruchirappalli. His research interests include power electronics and drives, renewable energy systems, WBG power Electronics and FACTS controllers.