A comparison of classical, robust, and decentralized control designs for multiple power system stabilizers

Several control design techniques, namely, the classical phase compensation approach, the mu -synthesis, and a linear matrix inequality technique, are used to coordinate two power system stabilizers to stabilize a 5-machine equivalent of the South/Southeast Brazilian system. The open-loop system has an unstable intearea mode and cannot be stabilized using only one conventional power system stabilizer. Both centralized and decentralized controllers are considered. The different designs are compared and several interesting observations are provided.