Decoupling Controller Design and Controllable Regions Analysis for the Space Vector Modulated Matrix Converter-Unified Power Flow Controller in Transmission Systems

Abstract

The flexible alternating current transmission systems (FACTS) devices are essential components of the transmission system to enhance the controllability and elevate the transfer capacity of the network. The unified power flow controller is known as the most versatile device in the FACTS family. This work studies a distinctive unified power flow controller (UPFC) structure based on the direct matrix converter to regulate the active and reactive power in a transmission system. In contrast to the conventional UPFC, there is no requirement for a bulky energy storage element in this structure. This results in various benefits including: decreased system volume, improved efficiency, prolonged lifetime, reduced maintenance and removal of the DC-link control. The full power controllable regions are analyzed and graphically obtained for the MC-UPFC, which facilitates the selection of proper UPFC ratings. The working principles and a model of the MC-UPFC are put forward and discussed, followed by explanations of direct space vector modulation (SVM) for this application. Based on the SVM modulation scheme, PID controllers are developed to control power flows in a double-line transmission system. In addition, decoupling controllers are derived by feeding back the coupling components into controllers. The numerical simulation results for a double-line transmission system corroborate the feasibility and effectiveness of the proposition.

Keywords::

• decoupling control
• FACTS
• matrix converter
• power flow controller
• transmission
• UPFC

Additional information

Notes on contributors

Jianwei Zhang

Jianwei Zhang received his bachelor degree in electrical engineering from the Northwest A&F University, Yangling, Shaanxi, China, in 2014. Since then, he has been working towards his Ph.D. degree in electrical engineering at the University of Technology Sydney (UTS), Sydney, New South Wales, Australia. From 2015, he has been working as a Casual Academic at the Faculty of Engineering and IT, UTS. His research interests include control of power electronic converters, matrix converters, microgrids and AC motor drives.

David G. Dorrell

David Dorrell has a BEng (Hons) degree in Electrical and Electronic Engineering from The University of Leeds (1988), MSc degree from The University of Bradford in Power Electronics Engineering (1989) and PhD degree from The University of Cambridge in Engineering (1993). He has held teaching positions with The Robert Gordon University, University of Reading, University of Glasgow and University of Technology Sydney. In 2015 he took up a post as Professor of Electrical Machines at the University of KwaZulu-Natal, Durban, South Africa. He has authored or co-authored 100 journal papers and over 250 conference papers as well as co-authored a book. His research interests cover the design and analysis of various electrical machines and also renewable energy systems.

Li Li

Li Li received his B.S. degree from Huazhong University of Science and Technology in 1996, M.S. degree from Tsinghua University in 1999, and Ph.D. degree from University of California, Los Angeles in 2005. From 2005 to 2007 he was a research associate at the University of New South Wales at the Australian Defence Force Academy (UNSW@ADFA). From 2007 to 2011, he was a researcher at the National ICT Australia, Victoria Research Laboratory, Department of Electrical and Electronic Engineering, The University of Melbourne. He joined the University of Technology Sydney in 2011 and currently he is an Associate Professor. Dr Li held several visiting positions at Beijing Institute of Technology, Tsinghua University and UNSW@ADFA. His research interests are control theory and power system control.

Youguang Guo

Youguang Guo received the B.E. degree from Huazhong University of Science and Technology, China in 1985, the M.E. degree from Zhejiang University, China in 1988, and the Ph.D. degree from University of Technology Sydney (UTS), Australia in 2004, all in electrical engineering. He is currently an associate professor with the School of Electrical and Data

Engineering, Faculty of Engineering and Information Technology, UTS. His research areas include measurement and characterization of magnetic properties of magnetic materials, numerical analysis of electromagnetic field, electrical machine design and optimization, power electronic drives and motor control.