Design of Fractional Order PID Controller for Load Frequency Control in Perturbed Two Area Interconnected System

Abstract

The vital concern of the load frequency control in an interconnected system is to minimize the frequency and tie-line scheduled power variations. A robust controller is required to overcome these concerns in a power system. This paper presents an interval fractional-order proportional integral derivative controller design technique for load frequency control in power system. The controller has been designed for frequency control of two area interconnected system using stability boundary locus method. The controller design involves perturbation in the system parameters (±50%) using the Kharitonov theorem rather than using fixed values. The analysis of the designed controller has been performed by changing system parameters such as governor constant, turbine time constant and step load perturbation (magnitude and location). Further, the performance of the controller has also been monitored under the effect of non-linearities (GRC and GDB). Simulation results illustrate that proposed controller gives better results than the conventional methods.

Keywords:

• load frequency control
• stability boundary locus
• Kharitonov theorem
• interval fractional order PID controller

Acknowledgment

This publication is an outcome of the R&D work undertaken in the project under the Visvesvaraya PhD scheme of Electronics & Information Technology, Government of India, being implemented by Digital India Corporation (formerly Media Lab Asia).

Additional information

Notes on contributors

Ruchika Lamba

Ruchika Lamba is currently Lecturer in the Electrical and Instrumentation Engineering Department, Thapar Institute of Engineering & Technology, Patiala. Mrs. Lamba obtained her M.E. in 2009 with Gold Medal from Punjab University, Chandigarh. She is pursuing her Ph.D. in the area of Control Systems from Thapar Institute of Engineering & Technology. She has about nine years of teaching and research experience in the area of Instrumentation and Control. Her current areas of research interest include robust control, fractional control and control systems.

Sunil Kumar Singla

Dr. Sunil Kumar Singla did his graduation (with honors) in Instrumentation Engineering from Sant Longowal Institute of Engineering and Technology, Longowal in the year 1998. He did his postgraduation (Instrumentation & Control Engineering) from National Institute of Technical Teacher Training and Research (formally TTTI) Chandigarh in 2000. He did his Ph.D. in the field of Biometrics from Thapar Institute of Engineering & Technology Patiala in the year 2011. He joined the Thapar Institute of Engineering & Technology (formally TIET) Patiala as a Lecturer in February 2000 in the department of Electrical and Electronic Engineering. Currently he is Associate Professor in the Department of Electrical and Instrumentation Engineering. His research interests include image processing, biometrics and control system.

Swati Sondhi

Dr. Swati Sondhi did her bachelor’s in Instrumentation Engineering in 2009 from M.J.P. Rohilkhand University Bareilly. She did her M.E. in Instrumentation Engineering from Thapar Institute of Engineering and Technology in 2011 and obtained her Ph.D. in 2015 from Indian Institute of Technology Roorkee. She is currently working as Assistant Professor in the Electrical and Instrumentation Engineering Department, Thapar Institute of Engineering & Technology, Patiala. Her current area of research interest includes reduced order modelling, fractional order control systems, robust control, robotics and image processing.