Improved Control Strategy for Bidirectional Single Phase AC-DC Converter in Hybrid AC/DC Microgrid

Abstract

This paper presents the improved control strategy with optimal switching scheme to improve the bidirectional converter's power flow control capability and to allow for different modes of operation in hybrid AC/DC microgrid. Also, this improved control strategy eliminates the need of PI controller for independent reactive power control. With the improvements in digital controllers, it is possible to implement complex control circuitry easily. The performance of bidirectional converter with improved control strategy is verified first in simulation environment and then on lab scale experimental set-up with the control circuit is implemented using hardware in loop in the real-time digital simulation platform. The simulation and experimental results for all the cases show that the controller is highly capable for power transfer between AC and DC grid with very fast response and also control reactive power without additional PI controller. Also, it maintains the current total harmonic distortion (THD) within standard limits.

Keywords::

• bidirectional converter
• hybrid AC/DC microgrid
• hardware-in-loop simulation
• improved control strategy

Additional information

Notes on contributors

Rakesh Gundabathini

Rakesh Gundabathini has received B.Tech in Electrical and Electronics Engineering from University College of Engineering, JNTU, Kakinada in 2013 and M.Tech in Electrical Engineering from Indian Institute of Technology Gandhinagar in 2016. He is presently working as Scientific Officer - C at Kudankulam Nuclear power project, NPCIL. His research interest includes power electronic application in power systems, microgrid and renewable energy.

Naran M. Pindoriya

Naran M. Pindoriya received the M.E. degree in Electrical Engineering from M. S. University of Baroda, Gujarat, India in 2003 and Ph.D. in Electrical Engineering from Indian Institute of Technology Kanpur, Kanpur, India in 2009. He was a research fellow in the Department of Electrical and Computer Engineering at National University of Singapore, Singapore in 2010. Presently, he is an Assistant Professor in Electrical Engineering at Indian Institute of Technology Gandhinagar, Gandhinagar, India. He is a senior member of the IEEE, Fellow of IETE and member of Institution of Engineers (India). His research interests include smart distribution grid, microgrids, load forecasting and energy management.