TUNING OF POWER-SYSTEM STABILIZERS USING GENETIC ALGORITHMS

Several techniques exist for developing optimal controllers. This pape r investigates the tuning of power system stabilizers (PSS) using gene tic algorithms (GA). A digital simulation of a linearized model of a s ingle-machine infinite bus power system at some operating point is use d in conjunction with the genetic algorithm optimization process. The integral of the square of the error and the time-multiplied absolute v alue of the error performance indices are considered in the search for the optimal PSS parameters. In order to have good damping characteris tics over a wide range of operating conditions, the PSS parameters are optimized off-line for a selected set of grid points in the real powe r (P)-reactive power (Q) domain. The optimal settings thus obtained ca n then be stored and retrieved on-line to update the PSS parameters ba sed on measurements of the generator real and reactive power. Time dom ain simulations of the system with GA-tuned PSS show the improved dyna mic performance under widely varying load conditions. (C) 1996 Elsevie r Science S.A.