Power System Stabilizers (PSS) are used to generate supplementary damping control signals for the excitation system in order to damp the Low Frequency Oscillations (LFO) of the electric power system. The PSS is usually designed based on classical control approaches but this Conventional PSS (CPSS) has some problems. The CPSS is usually designed based on a linear model of the plant for a particular operating point. However, power systems are inherently nonlinear and the operating point frequently changes. Therefore, CPSS performance may deteriorate under variations that result from nonlinear and time-variant characteristics of the controlled plant. In this paper, to develop a highperformance PSS for a wide range of operating conditions, meta-heuristic optimization methods such as  Particle Swarm Optimization (PSO) and Genetic Algorithms (GA) are used for tuning PSS parameters.  The proposed optimization methods are evaluated against each other at a multi machine electric power system considering different loading conditions. The simulation results clearly indicate the effectiveness and validity of the proposed methods.

1. Bouhamida M, Mokhatri A and Denai MA (2005) 

Power system stabilizer design based on robust 

control techniques. ACSE .J. 5, 33-41.

2. Chatterjee A, Ghoshal SP and Mukherjee V (2009) A 

comparative study of single input and dual input 

power system stabilizer by hybrid evolutionary 

programming.  World Congress on Nature & 

Biologically inspired Computing. pp: 1047-1059.

3. Dubey M (2007) Design of genetic algorithm based 

fuzzy logic power system stabilizers in multi machine 

power system. International Conf.  Soft Computing & 

Intelligent Sys. pp: 214-219.

4. Gupta R, Bandopadhya B and Kulkarni AM (2005) 

Power system stabilizer for multi machine power 

system using robust decentralized periodic output 

feedback. IEE Proc.-Control Theory Application. 152, 3 – 8.

5. Hwanga GH, Kimb DW, Leec JH and Joo Y (2008) 

Design of fuzzy power system stabilizer using 

adaptive evolutionary algorithm.  Engg. Applicat.  

Artificial Intelligence. 21, 86–96. 

6. Jiang P, Yan W  and Weigu (2008) PSS parameter 

optimization with genetic algorithms. DRPT (2008)

nanjing china. pp:  900-903.

7. Kundur P (1993) Power system stability and control. 

McGraw-Hill. Inc. NY. pp: 700-822.

8. Linda MM and Nair NK (2010) Dynamic stability 

enhancement with fuzzy based power system 

stabilizer tuned by hottest non-traditional optimization 

technique.  Second Intel. Conf. Computing, Commu. 

Networking Technol.  pp:  1-5.

9. Liu W, Venayagamoorthy GK and Wunsch DC (2005) 

A heuristic dynamic programming based power 

system stabilizer for a turbo generator in a single 

machine power system.  IEEE transactions on 

industry applications. 4,1377-1385.   

10. Mehdi Nikzad, Shoorangiz Shams Shamsabad 

Farahani, Mohammad Bigdeli Tabar, Mehdi Ghasemi 

Naraghi and Ali Javadian (2011) Adjustment of PSS 

in a multi machine power system based on particle 

swarm optimization technique. Indian J.Sci.Technol.

4 (8), 876-880. Domain site: http://www.indjst.org.

11. Mocwane K and Folly KA (2007) Robustness 

evaluation of H power system stabilizer.  IEEE PES 

Power Africa Conf.  Exhibi. pp: 16-20.

12. Nambu M and Ohsawa Y (1996) Development of an 

advanced power system stabilizer using a strict 

linearization approach.  IEEE Trans. Power Sys. 11, 813-818. 

13. Randy LH and Sue EH (2004) Practical genetic 

algorithms. Second edition, John Wiley & Sons.  pp:25-67.

14. Reza Hemmati, Sayed Mojtaba Shirvani Boroujeni, 

Hamideh Delafkar and Amin Safarnezhad Boroujeni 

(2011) Fuzzy load frequency control in multi area 

electric power system. Indian J.Sci.Technol. 4 (7), 

796-800. Domain site: http://www.indjst.org.

15. Sayed Mojtaba Shirvani Boroujeni, Babak Keyvani 

Boroujeni, Hamideh Delafkar, Elahe Behzadipour and 

Reza Hemmati (2011) Harmony search algorithm for 

STATCOM controllers tuning in a multi machine 

environment. Indian J.Sci.Technol. 4 ( 9), 1031-1035. 

Domain site: http://www.indjst.org.

16. Shayeghi H, Shayanfar HA, Safari A and Aghmasheh 

RA (2010) Robust PSSs design using PSO in a multimachine environment.  Energy Conversion & Mangt. 51, 696–702.

17. Shoorangiz Shams Shamsabad Farahani, Mehdi 

Nikzad, Mohammad Bigdeli Tabar, Mehdi Ghasemi 

Naraghi and Ali Javadian (2011a) Multi-machine 

power system stabilizer adjustment using genetic 

algorithms. Indian J.Sci.Technol. 4 (8), 881-885. 

Domain site: http://www.indjst.org.

18. Shoorangiz Shams Shamsabad Farahani, Mehdi 

Nikzad, Mohammad Bigdeli Tabar, Mehdi Ghasemi 

Naraghi and Ali Javadian (2011b) Multi-machine 

power system stabilizer adjustment using Simulated 

Annealing. Indian J.Sci.Technol. 4 (8), 886-889. 

Domain site: http://www.indjst.org.

19. Sil A, Gangopadhyay TK, Paul S and Maitra AK 

(2009) Design of robust power system stabilizer using 

H∞ mixed sensitivity technique.  Third Intel. Conf. 

Power Sys. India. pp: 1-4. 

20. Sudha KR, Vakula VS and Vijayasanthi R (2009) 

Particle swarm optimization in fine tuning of PID fuzzy 

logic power system stabilizer.  Intel. Conf.  Adv. In 

Computing, Control & Telecommu. Technol. pp: 356-358. 

21. Sumathi N, Selvan MP and Kumaresan N (2007) A 

hybrid genetic algorithm based power system 

stabilizer. Intel Conf.  Intelligent & Adv. Sys.  pp: 876-881.

22. Yassami H, Darabi A and Rafiei SMR (2010) Power 

system stabilizer design using strength pareto multiobjective optimization approach. Electric Power Sys. Res. 80, 838–846.