International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006
  • Published Articles: 2569

Full Length Research Paper

Voltage support and stability improvement using unified power flow controller tuned based on simulated annealing

Mehdi Nikzad*, Shoorangiz Shams Shamsabad Farahani, Mehdi Ghasemi Naraghi, Mohammad Bigdeli Tabar and Ali Javadian        
Department of Electrical Engineering, Islamshahr Branch, Islamic Azad University, Tehran, Iran.
Email: [email protected]

  •  Accepted: 08 August 2011
  •  Published: 23 September 2011


In this paper, the authors are willing to study the effects of unified power flow controller (UPFC) on voltage support and also stability enhancement at a multi-machine electric power system. Proportional-Integral (PI) type controllers are considered for UPFC control and the parameters of these PI type controllers are tuned using simulated annealing (SA).  In order to show the ability of UPFC in voltage control and also stability enhancement, the results of the system with UPFC are compared with the results without UPFC. Nonlinear time domain simulation results emphases on the ability of UPFC in simultaneous control of voltage and also stability enhancement


Key words: Unified power flow controller, voltage support, dynamic stability enhancement,multi-machine electric power system, simulated annealing.


FACTS, flexible AC transmission systemsUPFC, unified power flow controller; SA, simulated annealingLFO, low frequency oscillations;