Distributed Wind Energy Conversion System Interface to the Grid Using Cascaded Multi-Level Converter

ABSTRACT

In this paper, a distributed wind energy conversion system based on the cascaded H-bridge multi-level converter topology has been proposed to be used for the medium-voltage grid interface application. This includes load compensation and injection of real power requirement of the load. The load compensation includes reactive power compensation, load harmonic mitigation, and correction for the unbalancing problem. An algorithm has been proposed for generating references for the voltage source converter in current control mode in order to inject real power together with the reactive and harmonic components of the load. Modular structure of the wind turbine-alternator sets and cascaded multi-level inverter using H-bridges suits the distributed wind energy conversion system interface to the medium-voltage grid. The factors like equal distribution of switching stress and power losses, reduced power ratings of the inverter, redundancy, and high quality of inverter output voltage make the proposed arrangement efficient for high-power applications. The cascaded topology with phase-shifted multi-carrier pulse width modulation (PWM) has the features of increasing the effective switching frequency and reducing the ripple magnitude. The proposed scheme has been verified through the simulation study using power system transient analysis tool (PSCAD/EMTDC).

KEYWORDS:

• Cascaded multi-level converter topology
• Distributed system
• Grid interface
• Pulse width modulation
• Wind energy conversion system (WECS)

DISCLOSURE STATEMENT

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Chandra Sekhar Nalamati

Chandra Sekhar Nalamati received the bachelor's degree from PVP SIT, Vijayawada, India, in 2006, and the master's degree in electrical engineering with specialization in power electronics and ASIC design from Motilal Nehru National Institute of Technology, Allahabad, India in 2009.He worked as an electrical engineer about two years (from November 2009 to August 2011) in MIDMAC Contracting Co., WLL, Doha-Qatar. From July 2012 to December 2015, he was an assistant professor in GITAM University, Visakhapatnam, India. He is currently a research associate and working towards the PhD degree in the Department of Electrical Engineering, Motilal Nehru National Institute of Technology, Allahabad, India. His research interests include power electronics, multi-level, and bidirectional converters for renewable energy source applications.

E-mail: [email protected]

Paulson Samuel

Paulson Samuel received the bachelor of engineering (electrical) degree from the G.S. Institute of Technology and Science, Indore, India, in 1984, and the master of engineering in computer science and engineering and PhD degrees in electrical engineering from Motilal Nehru National Institute of Technology, Allahabad, India, in 1998 and 2013, respectively. From 1990 onwards, he has been a faculty member in the Department of Electrical Engineering, Motilal Nehru National Institute of Technology, where he is presently an associate professor. From 1984 to 1990, he was an engineer at the National Thermal Power Corporation, New Delhi, India. His research interests include power quality, distributed generation, automation, control of power converters, and multi-level inverters.

E-mail: [email protected]

Rajesh Gupta

Rajesh Gupta received the bachelor's degree from the Madan Mohan Malviya Engineering College, Gorakhpur, India, in 1993, the master's degree from the Birla Institute of Technology, Ranchi, India, in 1995, and the PhD degree from the Indian Institute of Technology, Kanpur, India, in 2007, all in electrical engineering. He is currently an associate professor with the Department of Electrical Engineering, Motilal Nehru National Institute of Technology, Allahabad, India. Prior to this from 1995 to 1999, he taught in the Institute of Engineering and Technology, Lucknow, and Govind Ballabh Pant Engineering College, Pauri Garhwal, India. His research interests include control of power electronics converters, multi-level converters, distribution system compensation, FACTS, and power conversion from renewable sources of energy. Dr Gupta is a regular reviewer for the IEEE Transcations on Power Electronics, the IEEE Transcations on Industrial Electronics, and IET Power Electronics. He volunteered as a Joint Secretary of the IEEE Uttar Pradesh Section for the year 2011 and 2012 and as a Secretary of the IEEE Joint Society Chapter of IE/PEL/CS for the year 2010 and 2012. Currently, he is a Vice-Chairman of the IEEE Uttar Pradesh Section. He is recipient of Outstanding Branch Counsellor Award by IEEE, of Region-10 (Asia-Pacific) for the year 2013 and Outstanding Section Volunteer Award by IEEE Uttar Pradesh Section for the year 2014.

E-mail: [email protected]