Optimal Coordinated Frequency and Voltage Control of CCGT-Thermal Plants with TIDF Controller

Abstract

This paper deals with unified method of voltage and frequency control of an interconnected three unequal-area systems with the Automatic Load Frequency Control (ALFC) and Automatic Voltage Regulator (AVR) loop. Every area comprises a reheat thermal and the combined cycle gas turbine (CCGT) plant. Concerning the pragmatic system, adequate governor dead band (GDB), boiler system, and generation rate constraint (GRC) are considered in all individual plants. The Tilt-Integral-Derivative with Filter (TIDF) controller is considered in the ancillary controller of the ALFC loops, core controller of the AVR loops, and air-flow, temperature controller of the CCGT Plants. The optimized controller gains are realized through the metaheuristic algorithm called Harris Hawks Optimization algorithm along with the integral square error as a performance index considering a 1% step load perturbation in Area-1. The critical analysis shows that the performance of the TIDF controller is superlative to the classical controllers, such as PI and PID, concerning all time-domain indices. With the TIDF controller, the impacts of the AVR loop, boiler system, and the CCGT plants are analyzed on the unified ALFC and AVR study separately. Sensitivity analysis unveils the sturdiness of the TIDF controller against the change in magnitude of the step load perturbation in Area-1. Finally, the proposed unified ALFC and AVR system of three unequal-area CCGT-thermal plants is analyzed with the OPAL-RT hardware set-up for its real-time validation.

KEYWORDS:

• Load frequency control
• Cross-coupling of ALFC and AVR
• Boiler system
• Combined cycle gas turbine
• Tilt-integral-derivative with filter controller

Additional information

Notes on contributors

Satish Kumar Ramoji

Satish Kumar Ramoji received his BTech degree in electrical and electronics engineering from National Institute of Science and Technology (NIST), Berhampur, affiliated to Biju Patnaik University of Technology, Rourkela, Odisha in 2008 and Master of Technology degree from JNTU, Kakinada, Andhra Pradesh in 2014. He is presently pursuing PhD at National Institute of Technology Silchar, Assam, India since 2018. His current research interests include power systems, automatic generation control, combined cycle energy systems, and renewable energies.

Lalit Chandra Saikia

Lalit Chandra Saikia received his BE from Dibrugarh University, Assam, in 1993. He started his teaching life as lecturer (Part-Time) in Jorhat Engineering College, Jorhat, Assam in 1997. In 2000, L C Saikia joined as a lecturer in Electrical Engineering Department, NIT Silchar. He received his MTech degree in power systems from Indian Institute of Technology, Delhi in 2007. He has achieved his PhD degree in electrical engineering from National Institute of Technology (NIT) Silchar, Assam in April 2012. He is currently working as associate professor in the Department of Electrical Engineering, NIT Silchar, Assam, India. He works in the field of power systems, soft computing application in power systems, power quality, power system control and operation. Email: [email protected]