Robust reconfigurable fault-tolerant controllers for PSS/FACTS using Kharitonov theorem and particle swarm optimization

The paper establishes a designed propose technique for reconfigurable fault-tolerant controllers applied on a flexible AC transmission system (FACTS) power system. A traditional power system stabilizer (PSS) of the generator excitation system and a controller of the thyristor-controller series capacitor (TCSC) are considered. Good operation of both controllers delivers the required dynamic performance of the system. However, faulty condition signifies a degraded control signal of one controller at a time. The designed scheme proposes that the parameters of one controller switch to some predetermined values if the other controller is faulty with any degradation percentage. Preserving definite settling time of the dynamic response is guaranteed against continual degradation of either controller as the design is implemented by Kharitonov theorem and particle swarm optimization (PSO). The proposed design represents an indirect adaptive PSS. Results represent distinct effectiveness of the proposed design in keeping the desired system performance under sound and different faulty conditions.