Robust decentralized design of power system stabilizers taking into consideration system uncertainties

In complex power systems, changes in network configurations, various loading conditions, etc., cause system uncertainties. Without considering such uncertainties in the design, the conventional power system stabilizers (PSSs) may deteriorate the system robust stability. To overcome this problem, the proposed design incorporates the uncertainty model in the system representation. Then, the PSSs in a multi-machine power system are arranged as the decentralized controller in a multi-input multi-output (MIMO) system. The robust stability margin of the closed-loop control system is guaranteed in terms of the MIMO gain margin and phase margin. Control parameters of PSSs are optimized by a tabu search. Non-linear simulation studies confirm the robustness of the designed PSSs against various uncertainties.