Robust design of multimachine power system stabilisers using tabu search algorithm

Robust design of multimachine power system stabilisers (PSSs) using the tab u search (TS) optimisation technique is presented. The proposed approach em ploys TS for optimal parameter settings of a widely used conventional fu;ed -structure lead-lag PSS (CPSS). The parameters of the proposed stabilisers are selected using TS in order to shift the system poorly damped electromec hanical modes at several loading conditions and system configurations simul taneously to a prescribed zone in the left hand side of the s-plane. Incorp oration of TS as a derivative-free optimisation technique in PSS design sig nificantly reduces the computational burden. In addition, the quality of th e optimal solution does not rely on the initial guess. The performance of t he proposed PSSs under different disturbances and loading conditions is inv estigated for multimachine power systems. The eigenvalue analysis and the n onlinear simulation results show the effectiveness of the proposed PSSs in damping out the local, as well as the interarea, modes and enhance greatly the system stability over a wide range of loading conditions and system con figurations.